Crime and Policing Act 2026 — Relevant documents: Economic Note 1009 – Counter Terrorism and National Security

Economic Note 1009 – Counter Terrorism and National Security
The measures assessed in this Economic Note for “Counter Terrorism and National
Security” are listed below in the summary table below.
Table 1: Measures included in “Counter Terrorism and National Security”.
Proposal  Measures included 
Measure 1A: Youth
Diversion Order
• Introducing a new youth diversion order to disrupt young
people (aged 21 and under) involved in terrorism related
offending and divert them from the wider criminal justice
system, including prosecution, given a lack of effective
existing tools.
• The order would impose both restrictive and supportive
measures on the young person to reduce the risk the
individual poses and support them away from terrorist
ideologies.
Measure 1B:
Terrorism and State
Threat Prevention
and Investigation
Measures:
unapproved articles
capable of being
used as a weapon
• Amending the Terrorism Prevention and Investigation
Measures Act 2011 to broaden the definition of
weapons.
• This will support the police and Security Service to
manage the risk from those involved in terrorism related
activity, by limiting access to bladed articles and other
articles capable of being used as a weapon.
• As part of this same measure, an equivalent amendment
will also be made to the State Threats Prevention and
Investigation Measures regime.
Measure 1C: Seizure
of any article
displayed in a public
place if it arouses
reasonable
suspicion that an
individual is a
supporter or
member of a
proscribed group.
• Amending section 13(1) of the Terrorism Act 2000 to
enable the police to seize any article displayed in a
public place if it arouses reasonable suspicion that an
individual is a supporter or member of a proscribed
organisation.
• Currently the seizure powers are dependent on the
article being used in criminal proceedings.
Measure 1D:
Application of
certain terrorism
offences (wearing of
uniform /displaying
an article) to
conduct in prisons
as well as other
prescribed places of
detention or
residence
• This measure widens the application of the existing
offence in section 13(1) of the Terrorism Act 2000 to
prisons as well as other prescribed places of detention
or residence.
• The section 13(1) offence criminalises the display or
wearing of articles in public places, such as images or
uniform, which would arouse a reasonable suspicion
that the individual is a supporter or a member of a
proscribed organisation.

Measure 1EManagement of
historic terrorist-
connected offenders
• Introducing a new power for the police, or the Secretary
of State, to apply to the courts to permit specific counter
terrorism risk management tools to be applied to a small
number of offenders that the government believes would
have been determined by the court as having a ‘terrorist
connection’ if this label had been available at the time of
their sentencing (mainly before 2009).

Economic Note NumberHO EN 1009
Title of regulatory proposal Crime and Policing Bill: Counter Terrorism
and National Security Measures
Lead Department/Agency Home Office
Expected date of implementation From Q1 2026
Origin Domestic
Date 10/02/25
Lead Departmental Contact CrimeandPolicingBillTeam@homeoffice.g
ov.uk
Departmental Assessment GREEN
Rationale for intervention, objectives and intended effects.
These measures make changes to counter terrorism legislation to ensure law
enforcement and intelligence agencies have the powers they need to keep us safe.
These measures will:
• Introduce a new tool for the police to intervene earlier in counter terrorism cases
involving young people, reducing the risk of young people being prosecuted for
terrorism offences.
• Make limited changes to police powers to disrupt terrorism related activity and
improve management of terrorist offenders.
• Extend an existing terrorism offence to reduce the risk of the prison estate being
a permissive place for radicalisation.
These measures are supported by operational partners and/or the Independent
Reviewer of Terrorism Legislation.
Policy options (including alternatives to regulation)
Option 0: ‘Do nothing’
Option 1: legislate for -
• Measure 1A: Youth diversion order.
• Measure 1B: Terrorism and State Threat Prevention and Investigation
Measures: unapproved articles capable of being used as a weapon.
• Measure 1C: Seizure of any article displayed in a public place if it arouses
reasonable suspicion that an individual is a supporter or member of a proscribed
group.
• Measure 1D: Application of certain terrorism offences (wearing of uniform
/displaying an article) to conduct in prisons as well as other prescribed places
of detention or residence.
• Measure 1E: Management of historic terrorist-connected offenders.
Option 1 is the g overnment’s preferred option as it meets the policy
objectives

Costs and benefit summary
The preferred option incurs various costs including device installation and support,
deradicalisation, subject monitoring, familiarisation, and resourcing for the prison
services, criminal justice system and operational partners.
Benefits include reduced prison pressure, operational savings in managing security
risks, efficiency savings and various other non-monetised security benefits.
Risks
Any considerable changes to the proposed volumes of affected individuals or their
behaviour would pose an analytical risk. Furthermore, proxies have been used to
model costs where actual costs could not be sourced. Mitigations are in place for
these risks.

Total Cost
(£m PV)
Transition
Cost (£m
Constant)
Cost to
Business (£m
PV)
omitted 0.24 0
Total Benefit
(£m PV)
NPSV
(£m PV)
BNPV
(£m PV)
EANDCB
(£m PV)
omitted -13.99 0 0
Price Base
Year PV Base Year Appraisal
period (Years)
Transition period
(Years)
2025-26 2025-26 10 1

Departmental sign-off (SCS)Anuj Matthew Date: 23/01/25
Chief Economist sign-off: Tim Laken Date: 10/02/25
Better Regulation Unit sign-off: Emma Kirk Date: 10/02/25

Evidence Base

A. Policy objectives and intended effects

Measure 1AYouth diversion order
1. Introducing a new youth diversion order (YDO) to disrupt young people (aged 21 years and
under) involved in terrorism-related activity and divert them from the wider criminal justice
system, including prosecution, given a lack of effective existing tools. For example, all tools
available for young people, particularly children, require either a criminal sentence or a guilty
plea (i.e., there are no diversionary options), which criminalises the young person even for
comparatively lower-level terrorism offending and can have a disproportionate ly negative
effect on their life chances. Furthermore, many tools rely on the young person to engage
voluntarily, which risks effective terrorism threat management where they refuse to engage.
The order would impose both restrictive and supportive measures on the young person to
reduce the risk the individual poses and support them away from terrorist ideologies. The
objective of the measure is also to reduce young people’s contact with the cri minal justice
system, improving their life chances, while managing the risk they pose in a more
proportionate manner. This follows a recommendation from the Independent Reviewer of
Terrorism Legislation (IRTL) in his Annual Report on the operation of the Terrorism Acts in
20211, that the government should consider alternative mechanisms for managing young
people who may have committed terrorism offences.
Measure 1B: Terrorism and State Threat Prevention and Investigation Measures :
unapproved articles capable of being used as a weapon
2. Amending the Terrorism Prevention and Investigation Measures Act 2011 ( TPIM 2011) to
broaden the definition of weapons. This will support the police and Security Service to
manage the risk from those involved in terrorism related activity, by limiting their access to
bladed articles and other articles capable of being used as a weapon. As part of this same
measure, an equivalent amendment will also be made to the State Threats Prevention and
Investigation Measures (STPIM) regime introduced by the National Security Act 2023 (NS
2023). These changes build on a recommendation made by the IRTL in his Annual Report
on the Terrorism Acts in 2022.2
Measure 1C: Seizure of any article displayed in a public place if it arouses reasonable
suspicion that an individual is a supporter or member of a proscribed group
3. Amending section 13(1) of the Terrorism Act 2000 (TACT 2000) to enable the police to seize
any article displayed in a public place if it arouses reasonable suspicion that an individual
is a supporter or member of a proscribed organisation. Currently the seizure powers are
dependent on the article being used in criminal proceedings. The measure will ensure that
the police can remove articles from public places even where those items are not connected
to an individual, without the need for the article to b e used in criminal proceedings. This
implements a recommendation from the IRTL’s Annual Report on the Terrorism Acts in
2022.3

1 Chapter 7.88, The Terrorism Acts in 2021:
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1140911/E028
76111_Terrorism_Acts_in_2021_Accessible.pdf
2 Chapter 8.40, The Terrorism Acts in 2022:
https://assets.publishing.service.gov.uk/media/674848622ac8a6da30723942/E03236791_-
_IRTL_Annual_Report_2022_Accessible.pdf
3 Chapter 9 Recommendations, The Terrorism Acts in 2022:
https://assets.publishing.service.gov.uk/media/674848622ac8a6da30723942/E03236791_-
_IRTL_Annual_Report_2022_Accessible.pdf

Measure 1DApplication of certain terrorism offences (wearing of uniform / displaying an
article) to conduct in prisons as well as other prescribed places of detention or residence
4. This measure widens the application of the existing offence in section 13 (1) of the TACT
2000 to prisons as well as other prescribed places of detention or residence. The section
13(1) offence criminalises the display or wearing of articles in public places, such as images
or uniform, which would arouse a reasonable suspicion that the individual is a supporter or
a member of a proscribed organisation. This implements a recommendation from the IRTL’s
report on Terrorism in Prisons published in 2022 4, following terrorist attacks committed by
serving prisoners or terrorist offenders released on licence from prison such as those at
HMP Whitemoor5, Fishmongers’ Hall6, and in Streatham7.
Measure 1E: Management of historic terrorist-connected offenders
5. Introducing a new power for the police, or the Secretary of State to apply to the courts to
permit specific counter terrorism risk management tools to be applied to a small number of
offenders that the government believes would have been determined by the court as having
a ‘terrorist connection’ if this label had been available at the time of their sentencing (mainly
before 2009).

B. Policy options considered, including alternatives to regulation

6. There are two options:
• Option 0: ‘Do nothing’
The Home Office do not consider that this is a feasible option given that it is essential
counter terrorism legislation is fit for purpose and ensures operational partners have
the powers they need to protect the public. A main aspect of this is considering
recommendations and feedback from operational partners on the evolving threat from
terrorism, and recommendations made by the IRTL, who has a statutory duty to
review the operation of the Terrorism Acts and other counter terrorism legislation. The
measures in Option 1 (legislate) are all provisions which are supported by operational
partners and/or the IRTL.
• Option 1 - legislate for -
Measure 1A: Youth diversion order.
Measure 1B: Terrorism and State Threat Prevention and Investigation Measures:
unapproved articles capable of being used as a weapon.
Measure 1C: Seizure of any article displayed in a public place if it arouses reasonable
suspicion that an individual is a supporter or member of a proscribed group.
Measure 1D: Application of certain terrorism offences (wearing of uniform / displaying
an article) to conduct in prisons as well as other prescribed places of detention or
residence.
Measure 1E: Management of historic terrorist-connected offenders.
Across these measures, the need for legislative change has been identified by operational
partners and/or the IRTL. Many of the changes are amending existing legislation and as

4 Recommendation 2, Terrorism in Prisons: https://terrorismlegislationreviewer.independent.gov.uk/wp-
content/uploads/2022/04/Terrorism-in-Prisons.pdf
5 https://www.bbc.co.uk/news/uk-england-cambridgeshire-54449183
6 https://www.bbc.co.uk/news/uk-england-london-57260509
7 https://www.bbc.co.uk/news/live/uk-51350195

such non-legislative approaches are not possible. It is concluded that, across the measures
above, legislative change is required to fulfil our policy objectives.
Option 1 is the government’s preferred option as it meets the policy objectives.

C. Past evaluations and rationale for government intervention

7. The physical threat of terrorism can cause serious injury and death for UK citizens. Beyond
the physical and emotional impact of terrorism on victims and their families, terrorism
causes wider economic damage through the fear caused by terrorism. This disr uption
through the fear caused by terrorism has economic and social ramifications through its
impact on people being unable to go about their day to day lives.
8. This is why CONTEST8 includes the aim to “reduce the risk to the UK and its citizens and
interests overseas from terrorism, so that people can go about their lives freely and with
confidence”. The below measures aim to provide legislative tools for law enforcement to
manage the risk posed by terrorist actors.
Measure 1A: Youth diversion orders.
9. Young people comprise an increasing proportion of counter terrorism investigations. The
Director General of Security Service highlighted recently that those aged under 18 now
comprise 13 per cent of individuals under investigation by Security Service as of October
2024, representing a threefold increase since January 2021 9. The numbers of arrests and
convictions of young people for terrorism, or terrorism related offences, have also
increased, though these likely underestimate the scale of problematic activity that falls
below the prosecution threshold. Most of the convictions are for online activity that
constitutes offences under section 2 of the Terrorism Act 2006 (TACT 2006) (dissemination
of terrorist publications) and section 58 of the TACT 2000 (collection of information).
10. The IRTL raised similar concerns about the rising number of young people (specifically
children) in counter terrorism casework in his annual report on the operation of the Terrorism
Acts in 2021, which led to his recommendation that the government consider introducing a
new “child violence diversion order” 10. More recently, the IRTL has publicly called for
alternative options to manage young people being investigated for terrorism offences.
11. Operational partners have highlighted that whilst there are existing tools to mitigate terrorist
risk, they are not well designed for young people. Where terrorist risk escalates Counter
Terrorism Policing (CTP) have highlighted that, whilst they may want to divert the young
person away from the criminal justice system, there is often no choice but to rely on criminal
processes and outcomes as a means of risk management. As a result, operational partners
support the introduction of a new youth-centred tool which could be implemented without
requiring a young person to enter the criminal justice system or admit to an offence. This
would reduce the risk of a young person being prosecuted for a terrorism offence, which, in
many cases, can have disproportionately negative consequences on their life chances.
12. Officials from the Home Office worked with operational partners, the Ministry of Justice
(MoJ), and Devolved Governments to consider the utility of existing interventions (such as
TPIMs and Youth Conditional Cautions (available in England & Wales)). The co nclusion
from this assessment was that whilst existing tools do provide some risk management
intervention, there is no risk management tool available which has been specifically

8 Counter-terrorism strategy (CONTEST) 2023 - GOV.UK: https://www.gov.uk/government/publications/counter-
terrorism-strategy-contest-2023
9 https://www.mi5.gov.uk/director-general-ken-mccallum-gives-latest-threat-update
10 Chapter 7.88, The Terrorism Acts in 2021:
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1140911/E028
76111_Terrorism_Acts_in_2021_Accessible.pdf

designed for the needs of young people whilst also tailored to mitigating terrorist risk, which
can present different challenges to other types of criminality. For example, some tools are
voluntary, which, whilst preferable, may not always be effective for individuals who are not
willing to comply, others do not cover the same types of activity that would be covered by
the YDO, and others have limited, or no, safeguards for young people.
13. Home Office officials have since worked with operational partners, the MoJ, the Youth
Justice Board, and Devolved Governments to develop the model for the YDO, including the
range of activity that would fall within scope of a YDO, the potential measures under the
order, the means of monitoring compliance with the measures and appropriate safeguards
governing the tool’s use. The measures that could be imposed under a YDO would include
restrictions on association with specific individual or groups (offline or online), mandatory
engagement with ideological mentors, or restrictions on accessing specific websites or
online apps.
14. New legislation would introduce a new power for police to apply to the courts for a YDO for
cases involving individuals under the age of 21 if specific grounds were met and the courts
considered it necessary and proportionate to manage the risk from the individual.
Subsequent statutory guidance would help practitioners in the application for and
implementation of a YDO.
Measure 1B: Terrorism and State Threat Prevention and Investigation Measures:
unapproved articles capable of being used as a weapon.
15. The TPIM 2011 supports the management of those involved in terrorism related activity who
cannot be prosecuted or deported to prevent them carrying out further terrorist related
activity. Schedule 1 to the TPIM 2011 sets out the measures which may be imposed should
a TPIM be imposed. These measures include a weapons and explosives measure which
prohibits owning, for example, guns, offensive weapons or explosives.
16. The TPIM 2011 does not allow the prohibition of the possession of bladed articles or other
articles capable of being used as a weapon, instead only where this would be defined as
an ‘offensive weapon’. An offensive weapon is defined as “an article made or adapted for
use for causing injury to the person or intended by the person in possession of it for such
use (by that person or another)”.
17. These changes build on a recommendation made by the IRTL, in his 2022 review on the
operation of terrorism legislation in relation to TPIMs.11
18. STPIMs were introduced by the NS 2023 and replicate the TPIM regime with a focus on
preventing an individual’s further involvement in foreign power threat activity, as defined at
section 33 of the NS 2023.12
19. The TPIM 2011 will be amended to support the police and Security Service to manage the
risk from those involved in terrorism related activity, by broadening the definition of weapons
within the Act. This will better support restricting TPIM subjects’ access to weapons and
other articles capable of being used as a weapon. An equivalent amendment will also be
made to the STPIM regime.
Measure 1C: Seizure of any article displayed in a public place if it arouses reasonable
suspicion that an individual is a supporter or member of a proscribed group.
20. Section 13 of TACT 2000 makes it an offence to wear any uniform, or wear, carry or display
an article (including publishing images online), in a way which would arouse reasonable
suspicion that the individual is a supporter or member of a proscribed organi sation. The

11 Chapter 8.40, The Terrorism Acts in 2022:
https://assets.publishing.service.gov.uk/media/674848622ac8a6da30723942/E03236791_-
_IRTL_Annual_Report_2022_Accessible.pdf
12 Section 33, National Security Act 2023: https://www.legislation.gov.uk/ukpga/2023/32/section/33

offence is an important disruption tool in countering support for proscribed organisations,
particularly in a public order setting.
21. The Counter Terrorism and Border Security Act 2019 made changes to provide a bespoke
power to seize articles covered by section 13. This was required as existing seizure powers
were dependent upon arrest, and arrest is not always the most suitable disruptive option
where a section 13 offence has occurred . For example, in a public order context this may
inadvertently escalate the situation.
22. In his annual report on the Terrorism Acts in 2022, the IRTL highlight ed a particular issue
with the seizure powers in a Northern Ireland (NI) context, as the police must consider it
necessary to seize the article to prevent any evidence associated with criminal proceedings
from being concealed, lost, altered or destroyed. The IRTL highlighted that articles which
may arouse support for proscribed organisations may appear in public places with no
connection to a specific individual, for example, the IRTL men tions the example of flags
being displayed on lampposts in NI.
23. As a result, the police may be unable to use the current section 13 seizure powers to remove
these articles, as there would be no prospect of a section 13 prosecution against any
individual and the purpose of the seizure is more likely to be to prevent the ongoing display
which can cause harm to communities.
24. This measure will make changes to the existing seizure powers in section 13 to ensure the
police can seize section 13 articles displayed in public places even where there is no
reasonable prospect of prosecution. Home Office officials have engaged with the Northern
Ireland Office, the Police Service of Northern Ireland (PSNI) and CTP on this measure and,
whilst the Department does not consider that this will result in a significant uplift in seizures
by the police, all stakeholders are supportive of making this change to improve the flexibility
of the seizure power.
Measure 1D: Application of certain terrorism offences (wearing of uniform / displaying an
article) to conduct in prisons as well as other prescribed places of detention or residence.
25. Part 2 of TACT 2000 provides a regime under which certain organisations are proscribed.
Section 13(1) of TACT 2000 makes it an offence to wear the uniform of a proscribed
organisation, or to display items or articles that are associated with a proscribed
organisation, such as the organisation’s flag.
26. Section 13(4) to (6) of TACT 2000 confer powers on a constable to seize articles, including
items of clothing, that are reasonably suspected to be evidence that the section 13(1)
offence has been committed.
27. The offence under section 13 (1) of TACT 2000 can be committed only in a public place.
Section 121 of TACT 2000 defines a public place as “a place to which members of the public
have or are permitted to have access, whether or not for payment”. Under this definition a
prison etc would not be considered a public place and as such the section 13(1) of TACT
2000 offence does not apply in these settings currently.
28. In April 2022, a review of Terrorism in Prisons in England and Wales produced by the IRTL
was published. One of the recommendations was to amend section 13 of TACT 2000 to
extend the section 13(1) offence to the prison setting 13. This measure will implement this
recommendation.
29. This measure will ensure that the section 13(1) offence is capable of being committed in the
settings listed below:
• Prisons
• Young offender institutions

13 Recommendation 2, Terrorism in Prisons: https://terrorismlegislationreviewer.independent.gov.uk/wp-
content/uploads/2022/04/Terrorism-in-Prisons.pdf

• Secure training centres
• Approved Premises 14
• Relevant military detention facilities
• Immigration Removal Centres.
Measure 1E: Management of historic terrorist connected offenders
30. Part 4 of the Counter Terrorism Act 2008 (CTA 2008) introduced a requirement for courts
to consider whether specified non -terrorism offences were committed with a terrorist
connection. If the court determines this was the case, then it must aggravate the sentence
and state in open court that the offence has been aggravated.
31. Specified non-terrorist offences were those listed in Schedule 2 to the CTA 2008, that the
judge considered had or may have had a terrorist connection, and which were committed
on or after its date of commencement of 18 June 2009. Following the attacks at
Fishmongers’ Hall and Streatham in November 2019 and February 2020 respectively, the
Counter Terrorism and Sentencing Act 2021 expanded this requirement so that the court
must consider whether there was a terrorist connection for all offences with a maximu m
penalty of more than two years’ imprisonment.
32. The CTA 2008 also introduced notification requirements for individuals with convictions for
terrorism offences or offences with a terrorist connection, to notify certain information to the
police and to keep that information up to date (such as their name, address, an d national
insurance number). For offenders with a terrorist connection, constables have the power to:
• arrest and detain a terrorist offender or a terrorist connected offender on suspicion of
a breach of licence conditions, pending a decision on whether or not to recall the
person to prison, if considered necessary to protect the public.
• stop and search a terrorist offender or terrorist connected offender who is released on
licence. The power applies if it is a condition of the offender’s licence that they submit
to a search, and the constable considers that the search is necessary to prot ect the
public.
33. There is currently no provision to add notification requirements and the powers of arrest
and personal search to the licence of an offender who committed a terrorism connected
offence before the commencement of the CTA 2008 on 18 June 2009 or who committed a
terrorism connected offence between 2009 and 2021 which fell outside the then specified
list in Schedule 2 to the CTA 2008
34. This measure will amend Part 4 of the CTA 2008 to allow the police or the Secretary of
State to apply to the court for a notification order on an offender where an offender was
sentenced before the commencement of the CTA 2008 on 18 June 2009 or between 2009
and 2021 for an offence which fell outside the then specified list in Schedule 2 to the CTA
2008. Offenders will be subject to the conditions and requirements listed in paragraph 32.

D. Appraisal

35. As the equivalent annual net direct costs to the public sector are less than +/- £20 million,
an Impact Assessment is not required for this intervention and an Economic Note has been
prepared instead.
36. This economic note ( EN) summarises the impact of the above legislative measures on
individuals and groups in the UK. The costs and benefits of each legislative measure are
compared to the ‘Do nothing’ option. These impacts have been assessed using HM

14 Accommodation mostly used for people on licence, but they also accommodate small numbers of people on bail
or community sentences. They have supervision for those deemed 'high risk'.

Treasury Green Book guidance. To make the estimates for each measure comparable, the
following conventions are adopted across the measures:
• Monetised costs and benefits are stated in 2025/26 prices.
• The Net Present Cost (NPC) and Net Present Benefit (NPB) of each measure has
been calculated for a ten-year period starting in 2025/26. A Net Present Social Value
(NPSV) is also provided below in the summary table
• A discount rate of 3.5 per cent is used when calculating economic costs.
• Costs are rounded to the nearest hundred pounds.
• Ranges are used, where appropriate, to account for uncertainty in the modelling.
• In the presentation of this analysis, central is the scenario that is estimated to be the
most likely to occur, given the stated assumptions. Low and high refer to extreme
scenarios which have a possibility to occur although unlikely.
• Data are taken from the Home Office, MoJ, Office for National Statistics, Youth Justice
Board, Magistrates Association, CTP and Operational Partners.
• Prison running costs are assumed to increase by around 3 per cent per year in real
terms over the ten -year appraisal period. This is based on prison performance data
published by the MoJ.15
• Annual prison and probation costs are assumed to be spread uniformly across the
year.
• Prisoners are assumed to start their sentences concurrently at the start of the year.
• In line with MoJ guidance, £525,000 (2025/26 prices) per adult prison place has been
included to account for prison building costs where a measure results in a net increase
in the number of prison places. Where a measure results in a net reduction in prison
places, the £525,000 has been included in prison savings.
• In line with HM Treasury Green Book guidance, an optimism bias adjustment of 20
per cent has been applied to all prison costs (building and running) to account for
potential uncertainty when estimating costs.
• The Readingsoft calculator is used in calculating familiarisation costs. To calculate
the cost of familiarisation, the estimated reading time of the information document was
multiplied by the labour cost and the volume of individuals required to read it.16
• In areas where explicit labour costs cannot be sourced, estimated labour costs have
been calculated by uplifting average wages to account for overheads.
• Familiarisation costs are only incurred in year 0 of implementation.
• Where costs and inputs are not explicitly known, suitable proxies have been used and
scrutinised to ensure appropriateness.
• See below for measure-specific inputs, assumptions, data sources and calculations.
Option 1
37. These measures will result in a range of costs and benefits . The moneti sed costs are
summarised below. It has not been possible to monetise all presented benefits as data are
not available.

15 https://www.gov.uk/government/publications/prison-performance-data-2022-to-2023
16 https://readingsoft.com/

38. The intention is that thes e counter terrorism measures produce non-monetised security
benefits, including:
• diverting young people from the criminal justice system where possible,
• preventing TPIM subjects from possessing offensive weapons,
• reduce the influence of proscribed organisations in public places,
• preventing prisons becoming permissive places for radicalisation.
39. By managing the risk posed by terrorism, this legislation may prevent terrorist activity
(including violent attacks) that have physical and emotional impacts on British citizens and
their assets. By reducing the risk of terrorism, these measures may reduce the disruption
of terrorism related fear which has economic and social ramifications through its impact
on people feeling unable to go about their day to day lives. Due to the difficulties in
estimating the future nature and scale of terrorism, it is not possible to calculate a realistic
reduction in terrorism as a direct result of these policy measures.
Table 2: Per-measure central values (£m) rounded to two decimal places (2025/26
PY, PV)
Measure Net Present
Benefits
Net
Present
Costs
Net Present
Social
Value
Measure 1A: Youth Diversion
Order
Have been omitted due to
operational sensitivity. - 13.04
Measure 1B: Terrorism and State
Threat Prevention and
Investigation Measures:
unapproved articles capable of
being used as a weapon
0.00 0.45 - 0.45
Measure 1C: Seizure of any
article displayed in a public place
if it arouses reasonable suspicion
that an individual is a supporter or
member of a proscribed group.
0.00 0.00 0.00
Measure 1D: Application of
certain terrorism offences
(wearing of uniform / displaying an
article) to conduct in prisons as
well as other prescribed places of
detention or residence.17
0.00 0.02 -0.02
Measure 1E: Management of
historic terrorist-connected
offenders
0.00 0.48 - 0.48
Source :Home Office own estimates, 2025
40. See below for more detailed description of the appraisal across the measures, split via costs
and benefits. It should be noted that there may be other consequences of this legislation
that have not been identified.
Measure 1A: Youth Diversion Orders
41. For reasons of operational sensitivity , the volume of individuals expected to be issued a
YDO cannot be disclosed . Consequently, only the ten -year NPSV of the measure is
presented in the summary table.

17 Currently only partially monetised costs and benefits for this measure. Monetised costs per offender have been
presented below while total monetised costs have been omitted. Further explanation is provided below.

Measure specific assumptions
42. The following assumptions have been used for the analysis of this measure:
• The YDO will be applicable to juveniles and young adults. The split between those
aged under 18 years and those aged 18 to 20 is expected to remain constant
throughout the ten-year appraisal period. The Home Office has assumed that there
is an approximate 50 per cent split between those aged under 18 and those aged 18
to 20 who will receive YDOs. This is based on the historic demographic split for arrests
of terrorism related offences. The relevance of this split is due to the difference in
prison running costs across cohorts, as it is assumed that those aged under 18 will
be sent to Youth Offender Institutions (YOIs), while those aged over 18 will be sent
to adult prisons.
• Operational partners have agreed that t he general juvenile reoffending rate (3 1 per
cent) is assumed to be a sensible proxy for t he number of individuals who are
prosecuted for breaching one, or more, of their YDO conditions. It is worth noting that
the police may deal with breaches through other means, such as through formal
warnings or variations of the YDO, for initial, or less serious, breaches, but this is not
reflected in this appraisal as it is assumed to be covered in monitoring costs. As a
result, the overall number of prosecutions and convictions for breaching a YDO may
be lower in practice.
• In the year ending September 2024, 85 out of 86 terrorism related trials resulted in
convictions. For the purposes of this appraisal, it is assumed that all individuals who
are prosecuted for breaching a YDO, will be convicted.18
• The custodial rate for being convicted of breaching a YDO is assumed to be 18 per
cent, similar to the custodial rate of breaching similar legal measures for individuals
aged between 10 to 20. Similar legal measures include youth rehabilitation order s
and detention and training orders.
• It is assumed that individuals who are convicted of breaching a YDO will receive either
a custodial sentence or a community sentence-like outcome but not both.
• The average number of individuals aged 10 to 20 being convicted and sentenced to
immediate custody each year for terrorism related offences is expected to remain
constant without the introduction of YDOs.
• The two proposed cohorts that have been considered in this appraisal are individuals
who have committed terrorism related offences and individuals who are involved in
terrorism related activity. Due to the similarities between the proposed cohorts of
individuals in this appraisal and individuals currently in custody for terrorism related
offences, it is assumed that a proportion of past convicted individuals could have been
diverted from custodial sentences if YDOs were available.
• It is difficult to estimate the actual volume of individuals who could have been diverted.
In consultation with operational partners, it is assumed that between 25 and 75 per
cent of individuals aged between 10 to 20, who are currently sentenced to immediate
custody for terrorism related offences, could have been diverted from custodial
sentences with the use of YDOs.
• Based on the above assumptions, Home Office assumes that an annual volume of
individuals are diverted from custodial sentences with the implementation of YDOs.
The high scenario assumes less individuals will be diverted while the low scenario
assumes a higher volume of individuals will be diverted.
• Home Office assumes that the individuals who are forecasted to be diverted by YDOs,
but would have received a custodial sentence otherwise, would have received a

18 https://www.gov.uk/government/statistics/operation-of-police-powers-under-tact-2000-to-september-2024

custodial sentence of 2.5 years, which is based on the lower estimate of the average
custodial sentence for terrorism related offences.19 The use of a lower estimate is due
to a significant volume of those aged under 18 , who have been convicted of a
terrorism related offence, receiving non-custodial or less severe sentences.
• Individuals who are convicted of breaching their YDO, receive a custodial sentence,
and are aged under 18 will receive a maximum custodial sentence of 6 months. They
will not be eligible for early release. This is consistent with MoJ guidelines for juveniles
sentenced to custody.
• Individuals who are convicted of breaching a YDO, receive a custodial sentence, and
are aged over 18, will receive a maximum custodial sentence of 2 years. They will be
eligible for early release. It is assumed that they will serve 16 months in custody and
the remaining 8 months on license. This is consistent with MoJ guidelines for adults
sentenced to custody.
• The costs of imprisoning a convicted adult are assumed to be different to the costs of
imprisoning a convicted juvenil e. Both types of costs have been sourced from MoJ
and uplifted in line with the methodology outlined in paragraph 36.
• Individuals who are convicted of breaching a YDO and receive a community sentence
outcome will receive a sentence similar to a youth rehabilitation order.
• The cost of administrating and monitoring an individual issued a community sentence
outcome is assumed to be similar for adults and juveniles.
• The approximate cost of a trial in a magistrate court for adults and juveniles are the
same.
• It is estimated that 52 per cent of individuals who breach their YDO will plead guilty ,
based on historic guilty pleas for terrorism related offences20. The rest are expected
to plead not guilty and require longer trials. The time taken for a trial to conclude is
based on historic casework.
• The cost of monitoring a juvenile and an adult is similar.
• All individuals are entitled to legal aid and are assumed to take it.
Costs
43. Monetised costs have been omitted for operational sensitivity. Instead, the methodology of
monetised costs has been presented below.
44. There are familiarisation costs for CTP . The number of CTP officers who need to be
familiarised is not known with any degree of certainty. It is assumed that between 25 per
cent and 75 per cent (with central estimate of 50 per cent) of CTP officers will be required
to familiarise themselves with the relevant legislation. The legislation length for Youth
Rehabilitation Orders has been used as a proxy for the legislative length of YDOs.
45. There are ongoing training costs, as CTP officers must be routinely trained how to handle
and enforce YDOs. As a proxy, the amount of time required to train CTP officers to handle
TPIM subjects has been used to model the cost of YDO training. This time has been
multiplied by the labour costs of CTP officers to arrive at the annual training cost per officer.
In the first year of implementation, the proportion of CTP office rs who require training is
taken from the volume of officers who need familiarising.
46. After the initial year, the number of officers who need training is the volume of new officers.
This has been calculated by multiplying the volume of CTP officers who need familiarising
by the leaving rate of CTP officers. As a proxy, the leaving rate of p olice officers (4.9 per

19 Ibid
20 https://www.gov.uk/government/statistics/operation-of-police-powers-under-tact-2000-to-september-2024

cent) has been used to model the leaving rate of CTP officers21. Training costs are incurred
in every year of the ten-year appraisal period.
47. There will be a cost incurred to the magistrate courts to issue a YDO. The cost of an
‘immediate guilty ’ plea magistrate trial has been used as an approximate proxy of the
increase in court resource costs. It is assumed that 100 per cent of individuals will be
entitled to legal aid which will generate a cost to the Legal Aid Agency (LAA). The average
legal a id cost of a Crown Court case has been used as a proxy for legal aid costs in
Magistrate Courts.
48. Similar to other civil and community -based measures, there are monitoring costs
associated with those issued YDOs to ensure that subjects are following all required
measures. Probation costs have been used as an appropriate proxy for the increase in
resource costs.
49. As part of the YDO, individuals will be required to attend deradicalisation focussed sessions
similar to Desistance and Disengagement Programme (DDP) and other Home Office -
accredited interventions. The costs of DDP interventions have been used as an appropriate
proxy for the annual cost of de-radicalisation sessions, although the interventions required
in practice may incur lower costs than DDP which is the most intensive type of intervention.
The cost of de-radicalisation is the greatest cost incurred.
50. A proportion of individuals are expected to be convicted for breaching their YDO. The
volume of individuals who breach their YDOs and are prosecuted will generate a cost to the
Crown Prosecution Service (CPS), Magistrates’ Courts and the LAA.
51. As mentioned in the measure specific assumptions, 18 per cent of those who breach their
YDOs are expected to be sentenced to immediate custody. They will incur a cost to the
criminal justice system through prison and probation costs. Costs for those aged over 18
and under 18 years have been separately calculated to account for the differences in
resources required to imprison them.
52. The remaining 82 per cent of individuals who breach their YDO are expected to be given
community sentence like outcomes. This will a incur a cost to the criminal justice system
through probation like costs.
53. Familiarisation and ongoing training costs for operational partners have not been monetised
due to the sensitivity of this information.
54. It has not been possible to monetise the wider societal impact of individuals breaching a
YDO as it is unknown how individuals will breach their YDO and to what extent. For
instance, by continuing to engage in terrorist activity. However, in the baseline o ption it is
likely that individuals would continue to pursue terrorist activity , so the costs should nullify
if the terrorist activities are assumed to be of equal severity and quantity.
Benefits
55. The methodology of benefits has been presented below. Numbers have been omitted for
operational sensitivity.
56. There are savings to the prison system from individuals being potentially diverted by the
implementation of YDOs. Overall, the measure is expected to cause a net reduction in the
number of individuals sentenced to prison. This is due to two decreasing effects. Firstly, the
measure will divert more individuals from prison than it introduces. Secondly, the proposed
sentence length for breaching a YDO is shorter than the average sentence length for
terrorism related offences, meaning individuals spend less time in prison than otherwise.
57. Combining the effects, the measure is expected to provide a net reduction in the annual
number of prison places needed. Consequently, the measure should provide an overall net

21 https://www.instituteforgovernment.org.uk/sites/default/files/2023-10/Retention-in-public-services.pdf

reduction in the resource requirements of the prison service. This applies to all age
demographics.
58. Furthermore, there are cost savings to the Crown Courts and CPS as there may be cases
where, rather than being taken forward to prosecution, the CPS consider it appropriate for
the police to apply for a YDO where terrorism related offences have been committed,
avoiding the need for a criminal trial.
59. It is important to recognise that the YDO would not prevent the CPS from taking forward a
prosecution if the relevant prosecutorial tests were met. The cost of prosecuting and
convicting an adult has been used as an appropriate proxy. Alongside court costs, there
are also savings for the LAA as they no longer need to provide legal aid to these individuals.
60. Operational savings to operational partners have not been monetised due to the sensitivity
of the information regarding resource usage per individual. It is believed that there are
significant operational savings to operational partners from the implementation of YDOs.
61. There are potentially additional non-monetised security benefits as individuals are diverted
from committing additional terrorism related offences that inflict harm on society. The
physical threat to people from terrorist activity can result in deaths or serious injury . The
objective of the YDO is to provide a tool for operational partners that will divert individuals
earlier from terrorist activities and could produce a much lower risk outcome than Option 0.
Reduced risk would be beneficial to UK citizens’ wellbeing. Although, it should be noted
that the risk that these young individuals pose and the effect of the measure in reducing the
risk cannot be explicitly quantified.
NSPV
Table 3: NPSV of measure 1A (£ millions, 2025/26 PY, PV)
Low Central High
NPSV -3.43 -13.04 -31.82
The granular breakdown of costs and benefits have been omitted due to operational
sensitivity
Source: Home Office, own estimates, 2025
Measure 1B: Terrorism and State Threat Prevention and Investigation Measures:
unapproved articles capable of being used as a weapon.
Measure specific assumptions
62. The following assumptions have been used for the analysis of this measure:
• The volume of new or revived TPIM issuances is expected to remain constant over
the ten-year appraisal period at 3.5 per year.
• The TPIM breach rate for other measures is expected to remain constant at 38 per
cent of issued TPIMs. This equates to 1.25 TPIM breaches per year.
• In the year ending September 2024, 85 out of 86 terrorism related trials resulted in
convictions. For the purposes of this appraisal, it is assumed that all individuals who
are prosecuted for breaching a TPIM, will be convicted.22
• There are currently no STPIM subjects, so these have been omitted from this analysis
as there is no indication that this is likely to change.
• Based on the historic custodial rate for prosecuted and convicted TPIM breaches, 87
per cent of breaches of this measure would result in a custodial sentence.
• Based on the average custodial sentence for individuals who breach a TPIM
measure, an individual who breaches the TPIM measure and receives a custodial

22 https://www.gov.uk/government/statistics/operation-of-police-powers-under-tact-2000-to-september-2024

sentence will be sentenced to 22.5 months in prison where it is assumed that they
will serve two-thirds of the sentence, before being released on license to serve the
remaining third in the community
• Based on the length of previous community sentences for TPIM breaches, the
average community sentence for an individual who breaches the measure and
receives a community sentence would be 7.7 months.
• All individuals are entitled to legal aid and are assumed to take it.
Costs
63. There are assumed to be no training costs for this measure, as CTP officers are already
trained in handling and enforcing TPIM measures similar to the proposed amendment.
Consequently, officers will not require any upskilling. The measure will not incur additional
monitoring costs as CTP officers have been previously monitoring TPIM subjects for similar
weapon measures. As a result, the measure will not generate additional monitoring burden,
and no resourcing costs.
64. There are familiarisation costs for CTP officers. It is assumed that the length of the
document that will be used to familiarise officers will be between 70 words to 500 words
(based on the length of previous TPIM measures). As it is difficult to estimate the actual
volume of officers that will need familiarising, a broad approach has been taken. it is
assumed that the document will need to be read by:
• 50 per cent to 100 per cent of constables (with central estimate of 75 per cent)
• 25 per cent to 100 per cent of sergeants (with central estimate of 50 per cent)
• 5 per cent to 15 per cent of senior officers (with central estimate of 10 per cent)
64. The discounted cost of familiarisation for CTP officers is between £0 and £ 2,400 with a
central estimate of £600 (2025/26 PY, 2025/26 PV).
65. The measure is expected to increase the average number of TPIM breaches per year
between 0 per cent and 100 per cent with a central estimate of 25 per cent. The decision
to place the upper bound of the analysis at 100 per cent additional breaches is to acc ount
for all unlikely but possible scenarios. This would result in an increase of 0 to 12.5 TPIM
breaches over the ten-year appraisal period, with a central estimate of 3.1 TPIM breaches.
These breaches would be split between individuals who receive custod ial sentences and
individuals who receive community sentences. The legal costs incurred to the CPS, the
LAA and the courts in prosecuting an individual who breaches the TPIM measure range
between £0 and £222,000 over the ten -year appraisal period with a central estimate of
£56,000 (2025/26 PY, PV).
66. As mentioned in the measure specific assumptions, an 87 per cent custodial rate would
result in between 0 and 10.8 individuals who breach th e measure being sentenced to
immediate custody over the ten -year appraisal period with a central estimate of 2.7
individuals over the ten-year appraisal period. The discounted cost of prison and license
costs for individuals who breach the measure is expected to be between £0 and £1,586,000
over the ten-year appraisal period with a central estimate of £396,000 (2025/26 PY, PV)
67. The remaining 13 per cent of individuals who breach the new TPIM measure are expected
to receive community sentences. The breaches would result in between 0 and 1.7
individuals being sentenced to community sentences over the ten -year appraisal period
with a central estimate of 0.4 individuals. This would incur a discounted cost to the justice
system between £0 and £6,200 over the ten-year period with a central estimate of £1,600
(2025/26 PY, PV).
68. The historic TPIM appeal rate is extremely low, and no subject has appealed a measure
similar to the one presented. As a result. it is not believed that the inclusion of this measure
will create additional appeals. Appeals have not been included in monetised costs.

69. The ten-year total discounted costs for this measure ranges between £0 million and £1.82
million, with a central estimate of £0.45 million (2025/26 PY,2025/26 PV)
Benefits
70. There are no monetised benefits to this measure.
71. This measure could provide non -monetised benefits including additional security benefits
from the reduction in risk that TPIM subjects pose to the UK. Although currently
unquantifiable, TPIM subjects could pose a substantive risk to the UK, as for a TPIM to be
imposed, there must be reasonable belief that the individual has been involved in terrorism
related activity.
72. The measure could provide greater risk management of TPIM subjects by providing the
legal means to limit the access of the subjects to offensive weapons that could harm British
citizens or property. As a result, the potential risk that TPIM subject s pose to UK citizens
may be reduced by this measure. It should be noted that it is not currently possible to
quantify the risk reduction that the measure may provide.
NPSV
Table 4: Total costs and benefits of measure 1B and NPSVs (£ millions, 2025/26
PY, PV)
Low Central High
Legal Costs 0.00 0.06 0.22
Prison costs 0.00 0.39 1.56
Probation costs 0.00 0.01 0.04
Familiarisation costs 0.00 0.00 0.00
Total costs 0.00 0.45 1.82
Total benefits 0.00 0.00 0.00
NPSV 0.00 -0.45 -1.82
Source: Home Office, own estimates, 2025
73. The net present social value of this measure ranges between £ 0 million and -£1.82
million, with a central estimate of -£0.45 million (2025/26 PY, PV)
Measure 1C: Seizure of any article displayed in a public place if it arouses reasonable
suspicion that an individual is a supporter or member of a proscribed group.
74. Our initial assessment, based on engagement with PSNI and CTP, is that the new seizure
power will most likely be used in Northern Ireland, and the appraisal focuses on the impact
within Northern Ireland. CTP have been consulted and they do not expect this measure to
be regularly used in Great Britain.
Costs
75. As the seizure of articles will not be used in criminal proceedings, there will be no additional
costs to the criminal justice system from individuals being prosecuted.
76. All Northern Irish police officers will be familiar with section 13 of TACT 2000. The changes
to legislation are relatively minimal with less than 40 words being added to the existing
legislation. Consequently, the Home Office has assumed that the time taken to familiarise
officers will be less than one minute. As a result, the marginal familiarisation costs will be
zero.
77. A similar logic applies to training costs as PSNI officers will not require any upskilling to use
section 13 powers. The measure is also likely to introduce a new destruction power for
relevant articles seized. However, this is unlikely to result in additional training costs to PSNI
officers given that they will be familiar with destroying harmful articles in other contexts.

78. The volume of additional seizures made under section 13 is expected to be minimal.
Furthermore, in line with the previous Counter Terrorism and Border Security Bill Impact
Assessment23, the time taken to remove and destroy the article is assumed to be zero. As
a result, it is assumed that the measure will not provide any additional burden to officers.
79. This results in a total net present cost of £0.00 million (2025/26 PY, PV).
Benefits
80. There are currently no monetised benefits to this measure. A potential non -monetised
benefit of the measure is the increase in the police’s flexibility to respond to the actions of
proscribed organisations, as well as the decreased visibility of articles relating to proscribed
organisations which could potentially lead to lower levels of support. As a consequence,
the public’s confidence in the police’s ability to respond to the actions of proscribed
organisations could increase, leading to reduced community tensions.
NPSV
81. The net present social value of this measure is £ 0.00 million over the 10-year
appraisal period.
Measure 1D: Application of certain terrorism offences (wearing of uniform / displaying an
article) to conduct in prisons as well as other prescribed places of detention or residence.
Broad approach to appraisal
82. The Home Office has been unable to monetise the total costs generated by the measure
due to the uncertain volume of potential offences and offenders expected under an
extended section 13(1) of TACT 2000.
83. There is currently no centrally recorded data of instance s of prison staff detecting section
13 articles within a prison setting, making it difficult to estimate the volume of
offences/offenders. Furthermore, the IRTL noted in his “Terrorism in Prisons” report24 that
due to the nature of the offence in a prison setting, it is often difficult to attribute the offence
to a specific individual (for example, the possession of proscribed organisations ’ flags in
shared cells).
84. As a result, even if it was feasible to estimate the prevalence of the offence, it would be
difficult to estimate the volume of connected offenders. In addition, the Home Office have
not been able to identify any suitable proxies that could reliably indicate the potential volume
of offences/offenders that will be prosecuted. Consequently, in the absence of volumes, the
department cannot reliably monetise the measure’s impact on the police, legal system and
prisons.
85. However, an estimate of the monetised cost per offender is presented below, as suitable
estimates of the unit costs associated with an extended section 13(1) of TACT 2000 are
available.
86. Additionally, reliable estimates of total familiarisation and training costs have been
presented as it is possible to reliably estimate those costs.
Measure specific assumptions
87. The following assumptions have been used for the analysis of this measure:
• As part of the Crime in Prison Referral Agreement25, if a crime is classed as a
terrorism or terrorism-connected offence, it is mandatory for prisons to refer an
offence committed by a prisoner to CTP to investigate and seek prosecution. As this

23
https://assets.publishing.service.gov.uk/media/5b9bd9ffed915d6efa0000b4/CTBS_Bill_Impact_Assessment_Lord
s_Introduction.pdf
24 https://assets.publishing.service.gov.uk/media/6267f916d3bf7f55c910e84e/terrorism-in-prisons.pdf
25 https://www.gov.uk/government/publications/handling-crimes-in-prison-protocol/crime-in-prison-referral-
agreement

provision will be a terrorism offence, it is assumed that 100 per cent of offenders will
be referred to CTP and investigated.
• The proportion of offenders that CTP decide to prosecute is unknown as the decision
to prosecute is based on operational considerations. If offenders are not prosecuted,
they would be processed through the prisons’ adjudication (prison discipline) system.
There is no available prox y for th e proportion of offenders as there are no readily
available statistics regarding the number of prison referrals that result in prosecution.
• As the cost of prosecution is significantly greater than the cost of the internal
adjudication system and the proportion of offenders that CTP decide to prosecute is
unknown, this appraisal takes a conservative approach 26. It assumes that all
individuals will be prosecuted. Only the costs of prosecuting offenders are presented
here but it should be noted that not all processed offenders will be prosecuted.
• If convicted of an offence under an extended section 13(1) of TACT 2000, a proportion
of offenders will be given an additional custodial sentence to serve consecutively to
their original sentence27. The exact proportion of offenders given additional custodial
sentences is unknown and will be dependent on a variety of aggravating factors.
• For context, the historic custodial rate for an unauthorised possession of a mobile
phone within prison offence for adults is 86 per cent while the historic custodial rate
for possession of an offensive weapon in prison for adults is 91 per cent28. As a result,
it is assumed that the vast majority of those convicted will be given custodial
sentences between the above rates (8 6 to 91 per cent). The remaining 9 to 14 per
cent will be given fines29.
• If prosecuted and convicted for breaching this offence and given a custodial sentence,
the individual would receive a custodial sentence of up to six months. This is the
maximum sentence for this offence. It is difficult to specify what the average sentence
will be. As a result, this appraisal has adopted a conservative approach30.
• This appraisal assumes that all custodial sentence lengths for th e breaches of an
extended section 13(1) of TACT 2000 will be six months. As the additional sentence
will be served consecutively to their original offence, it is assumed that all convicted
individuals who are given custodial sentences, will serve an additional six months in
prison.
• In the year ending September 2024, 85 out of 86 trials for terrorism related offences
resulted in convictions. For the purposes of this appraisal, it is assumed that all
individuals who are prosecuted for breaching this measure, will be convicted.31
Costs
88. Prison officers will need to become familiar with any relevant guidance. It is assumed that
the word length of a document used to familiarise officers with section 13(1) of TACT 2000
will be between 900 and 1000 words. This is based on:
• the word length of a section of the current guidance relating to the control of prohibited
items in prisons and32

26 In that costs are likely overestimated
27 Based on totality sentencing guidelines, an additional custodial sentence will be served consecutively to the
original sentence.
28 Custody rate includes all prisoners. The rate is not specific to terrorism related offenders.
29 In policy appraisal more generally, if an individual is convicted and given a fine, there is no economic cost as it is
simply an economic transfer.
30 In that costs are likely overestimated
31 https://www.gov.uk/government/statistics/operation-of-police-powers-under-tact-2000-to-september-2024
32 Managing conveyance of unauthorised and illicit items policy frameworks (open and closed prisons) - GOV.UK:
https://www.gov.uk/government/publications/managing-conveyance-of-unauthorised-and-illicit-items-policy-
frameworks-open-and-closed-prisons

• the word length of section 13 of the TACT 2000 legislation33.
89. As it is difficult to estimate actual volumes, a range of between 25 and 75 per cent has been
used to estimate the proportion of prison officers needed to be familiar with the new
legislation, with a central estimate of 50 per cent. In line with the method outlined in
paragraph 36 above, the total cost of familiarising prison officers is estimated to be between
£2,500 and £ 50,000, with a central estimate of £ 18,000. There will be no familiarisation
costs for CTP officers as they will be familiar with the application of section 13 in a public
setting.
90. There will be no training costs as prison officers are trained in the procedures regarding
searching and seizing similar prohibited items. CTP officers are trained in prison referrals
and investigation of section 13(1), TACT 2000 offences.
91. It is assumed that the measure would not increase the resource burden on HM Prison and
Probation Service ( HMPPS) having to conduct additional searches . Prison officers will
already be conducting cell searches as part of their routine operations, and it is assumed
that the number of additional searches carried out will be zero.
92. However, the introduction of the measure would increase the resource burden on HMPPS
if prohibited items are found as prison officers would have to process the offender and any
accompanying evidence. Consequently, the measure generates a labour cost to HMPPS –
which is in the firm of the opportunity cost associated with the time required for relevant
form filling - by increasing the workload of prison officers. Based on:
• the number of forms that need to be filled out as part of an adjudication process,
• the average speed of an individual completing the form and
• the average hourly labour cost of a prison officer.
93. The additional labour cost associated with processing the offender and any accompanying
evidence is estimated to be between £26 and £35 per offender.
94. Additional costs will be incurred by CTP if an offence under an extended section 13(1) of
TACT 2000 is referred. The exact costing for this referral is unknown . The estimate used
here is based on police investigation costs of other comparable crimes34. The cost of a
referral to CTP is estimated to be between £300 and £7,500 , with a central estimate of
£1,300.
95. Regardless of whether the prison refer s an offender to the police or not, the offence will
generate a cost to the prison if the prison decides to place the prisoner on report and an
adjudication hearing takes place 35. Based on data from MoJ, the cost of a single
adjudication hearing is estimated to be between £92 and £178 per offender depending on
the region and complexity of the offence.
96. Costs will be incurred by the legal system as offenders will be prosecuted and sentenced
for committing offences under an extended section 13(1) of TACT 2000. The average cost
per offender is estimated to be between £21,000 and £25,000 which is incurred by the LAA,
CPS and HM Courts and Tribunals Service . There will be additional costs to HMPPS in
enabling prisoners to attend proceedings. The cost of transporting a prisoner is estimated
to be between £1,400 and £1,800, with a central estimate of £1,600. Transport costs include
labour plus other miscellaneous expenses.36
97. As it assumed for the purpose of this analysis, offenders who are convicted and sentenced
to custodial sentences will serve an additional six months in prison, the measure will

33 Section 13, Terrorism Act 2000: https://www.legislation.gov.uk/ukpga/2000/11/section/13
34 Comparable crimes include possession of drugs, possession of offensive weapons and miscellaneous crimes
against society.
35 Any adjudication would be adjourned whilst the police are investigating to avoid double jeopardy
36 This is based on the transport costs for similar offences.

generate a cost to HMPPS to imprison the individual. As stated in paragraph 36 the annual
running costs of holding a prisoner are assumed to be spread uniformly across the year.
Based on MoJ guidance, it costs around £ 32,000 to hold a prisoner in a closed prison for
six months37. Furthermore, as the prisoner is being held longer than first expected, prisons
must find additional capacity to house other prisoners.
98. As a result, the measure is expected to increase the capacity requirements of the prison
system, resulting in the need to build new prison places. As stated in paragraph 36, the
estimated cost of building a new prison place is £ 628,00038. As a result, the cost to the
prison service in implementing the additional custodial sentence is £660,000 per offender.
99. Overall, the monetised cost per offender who is prosecuted and convicted is between
£0.02 million and £0.68 million with a central estimate of £0.70 million39.
Benefits
100. A non-monetisable benefit of the measure is the potential improved management of terrorist
risk posed by offenders within and outside of prisons.
101. The 2019 terror attack in HMP Whitemoor and the subsequent 2022 “Terrorism in Prisons”
report by the IRTL 40, highlighted the risk of terrorist violence within prisons. By enabling
prisons to exercise greater control over prisoners’ ability to display the potentially
radicalising material associated with proscribed organisations in prisons, the measure could
reduce a proscribed organisation’s influence within and outside of prisons. The ‘Terrorism
in Prisons ’ report suggests that several past terrorism offences have been linked to
associations or ideologies formed in prison.
102. Reducing the influence of proscribed organisations may reduce the risk that these
organisations pose to UK citizens’ safety and wellbeing, particularly when affiliated
offenders are released from prisons. Several of the last successful terrorist attacks in the
UK were carried out by current/former prisoners. As a result, reducing the risk of
radicalisation within prisons may reduce the risk that prisoners pose to the public when
released.
103. The IRTL highlighted that the public’s confidence in the criminal justice system is shaken if
terrorism is allowed to occur in prisons . If this legislation allows prisons to have a better
control of proscribed organisations within prison settings, improved confidence in the
criminal justice system which may translate to the reduced fear of terrorism among the
general public.
104. However, the analysis presented here has been unable to quantify nor mon etise the
measure’s benefits.

37 This includes a 20 per cent optimism bias.
38 This includes a 20 per cent optimism bias.
39 The lower bound being set at £0.02 million is based on the stated assumption that not all convicted offenders will
be given additional custodial sentences. Instead, these convicted offenders will be given fines. However, as most
convicted offenders will be given additional custodial sentences, the central estimate assumes that the offender
will be given a custodial sentence. The central estimate of cost includes the additional costs of custodial
sentences.
40 https://assets.publishing.service.gov.uk/media/6267f916d3bf7f55c910e84e/terrorism-in-prisons.pdf

Table 5Total costs per prosecuted offender of measure 1D (£ millions, 2025/26
PY)
Low Central High
Prison costs 0.00 0.00 0.00
Court costs 0.02 0.02 0.03
CTP referral costs 0.00 0.00 0.01
Additional custodial sentence costs 0.0041 0.54 0.54
Total costs 0.02 0.56 0.57
Total benefits 0.00 0.00 0.00
NPSV per offender -0.02 -0.56 -0.57
Source: Home Office, own estimates,2025
Measure 1E: Management of historic terrorist-connected offenders
Costs
105. Based on discussion with CTP, the maximum number of offenders that this measure could
apply to is 40 offenders. However, CTP have highlighted:
a. that not all offenders will have this measure applied; and
b. the rate that which it will be applied is highly uncertain. The analysis presented here
employs a low (one offender) to central (15 (offenders) to high (40 offenders) range.
106. The timing of when, during a ten-year policy appraisal period, the measure could be applied
by CTP is equally uncertain. As a result, the number of offenders which this tool is applied
to per year is expected to be between 0.1 and 4 offenders, with a central estimate of 1.5.
107. As referenced in paragraph 34, the police or the Secretary of State will be able to apply to
the courts to impose the terrorist notification. This will incur a cost to fulfil the additional
court documents required. The cost of producing a legal document has been calculated by
multiplying the labour hours required to complete by the wage of the officer that completes
the documents.
108. For the low estimate, the wage rate of a constable has been used while the high estimate
uses the wage rate of a sergeant. Overall, the completion of the legal documents is
expected to take between 8 and 16 hours. Overall, the discounted cost of producing legal
documents over the ten -year appraisal period is expected to be between £1,300 and
£78,000, with a central estimate of £24,000 (2025/26 PY, PV).
109. The measure will incur legal costs as the courts must be satisfied beyond “reasonable
doubt” that the offender’s offence had a necessary connection to terrorism. This generates
legal costs to CTP including the initial legal costs and cost of appointing counsel, the use
of closed material procedure (CMP)42, the cost of defending a judicial review and time cost
of CTP attendees. The total of these costs (per offender) is expected to be between £1,500
and £103,000. This results in total legal costs for CTP of between £1,500 and £410,000 per
year, with a central estimate of £50,000.
110. Additionally, prison transport costs are incurred by HMPPS to enable prisoners to attend
the hearings to determine whether the notification requirement should be applied, although
released offenders will not require transport. The ten -year discounted cost of transporting

41 As stated above, in the low scenario, it is assumed that the offender does not receive an additional custodial
sentence.
42 A CMP allows courts to protect sensitive material in civil proceedings when national security or other public
interests are at stake

prisoners is expected to be between £0 and £63,000 (2025/26 PY, PV). The costs incurred
to HMPPS include staff pay and other costs associated with the transport of prisoners.
111. Lastly, the measure is expected to increase the cost of a prisoner release by between £0
and £800 per affected offender, with a central estimate of £300 per offender. The cost is
incurred as officers are required to complete a part 4 notification as part of the offender’s
release, which incurs a labour cost (see paragraph 3 4). This produces a discounted over
the ten-year appraisal period between £200 and £ 7,400 with a central estimate of £2, 800
(2025/26 PY, PV).
112. This results in a total net present cost of between £0.01 million and £3.69 million,
with a central estimate of £0.48 million (2025/26 PY, PV).
Benefits
113. There are no monetisable benefits to this measure.
114. The measure should provide non -monetised security benefits by helping the police and
probation service manage the risk posed by the specific cohort of historic terrorist -
connected offenders upon release from custody. Although, the Home Office have been
unable to quantify the potential decrease in risk posed by historic terrorist connected
offenders.
NPSV
Table 6: Total costs and benefits of measure 1E and NPSVs (£ millions, 2025/26
PY, PV)
Low Central High
Increased cost of prison releases 0.00 0.00 0.01
Cost of producing court documents 0.00 0.03 0.10
Legal costs to CTP 0.01 0.43 3.53
Prisoner attendance costs 0.00 0.02 0.06
Total costs 0.01 0.48 3.69
Total benefits 0.00 0.00 0.00
NPSV -0.01 -0.48 -3.69
Source: Home Office,own estimates,2025
115. The net present social value of this measure ranges between - £0.01 million and -
£3.69 million, with a central estimate of - £0.48 million (2025/26 PY, PV)
BNPV and EANDCB
116. The monetised costs across all measures have no impact on business , so both the
Business Net Present Value (BNPV) and the equivalent annual net direct cost to business
(EANDCB) are zero for all measures.

E. Wider impacts

Equalities
117. An Equalities Impact Assessment across measures has been carried out in addition to this
EN. Please see this for further detail.

Better Regulation
118. These proposals are not considered to be regulatory provisions and are out of scope of the
Small Business Enterprise and Employment Act 2015.
Environmental Impact Assessment
119. The Home Office expect there to be no environmental impacts as a result of the options
within this EN. The policies meet the environmental principles in accordance with the
Environment Act 2021.
International Trade
120. There are no international trade implications from the options considered in this EN.

F. Sensitivity
121. None of the measures in this EN are regulatory provisions as defined under the Better
Regulation Framework. The equivalent annual net direct costs to the public sector are less
than +/- £20 million, so an IA is not required. This Economic Note has been produced
instead and contains proportionate analysis outlining the main costs, benefits, and NPSV
calculations.

G. Risks
122. Overall, ranges have been used to account for most of the uncertainty surrounding figures
with anticipated costs and benefits being relatively small. However, to account for where
assumptions may lack certainty, sensitivity analysis has been conducted and presented
below.
123. It should be noted that sensitivity analysis for measure 1A will not be presented due to
operational sensitivity.
Measure 1B: Terrorism and State Threat Prevention and Investigation Measures:
unapproved articles capable of being used as a weapon
124. Currently, it is assumed that the custody rate of breaching the proposed TPIM measure is
87 per cent which is based on the custody rate of TPIM breaches. If the assumption is
relaxed and it is assumed that all convicted individuals are sentenced to immediate custody,
for instance, if judges believe that convicted individuals pose a severe risk to the public.
125. The discounted costs would increase between £0 and £165,000 over the ten-year appraisal
period (2025/26 PY, PV). The majority of these costs would stem from additional prison
costs including building more prisons. However, as the imprisonment of these ind ividuals
could provide greater security benefits compared to a community sentence, it could be
argued that the non-monetised benefits would increase in tandem with the increased costs.
126. Currently, it is assumed that the number of TPIMs issued per year stays constant. If the
number of individuals who are issued TPIMs doubles, the expected monetised NPSV would
decrease between £0 and £1.35 million over the ten-year period. The majority of the costs
generated would be due to an increase in the number of potential breaches.
127. General analytical risks, as well as measure-specific analytical risks, are presented below
with brief descriptions of how the risk was mitigated.
Measure 1A: Youth Diversion Orders.
The net effect on prison places – volume of individuals being issued YDOs
128. The actual volume of individuals issued YDOs could significantly differ from expected
volumes. With an increased number of individuals being issued YDOs, there could be a
potential increase in the number of individuals who breach their YDO and are imprisoned

as a result . However, by following existing youth justice frameworks , practitioners are
unlikely to seek to prosecute for an offence in respect of most breaches, instead favouring
informal resolutions before seeking variations to the order or considering the imposition of
other community sentences. There is a risk that the measure imprisons more individuals
than it diverts, however , we found that, even in the most extreme scenarios, YDOs are
expected to divert more individuals from prison than it introduces.
129. The actual number of YDOs issued must exceed the proposed number by a significant
amount before the measure is expected to have a net positive effect on expected prison
places. The ranges cover any extreme but possible scenarios where the number of YDOs
increase significantly.
The net effect on prison places - volume of individuals being diverted by YDOs
130. YDOs could divert fewer individuals than estimated. There is a risk that individuals are not
diverted as the offences that they commit are too severe or the use of a YDO would be
inappropriate. As a result, those individuals may end up with a criminal conviction and
sentenced to prison. Consequently, the measure may divert fewer individuals from prison
then it sends.
131. Similar to above, the Home Office have taken a relatively large range of possible volumes
of individuals diverted. Overall, even in the most extreme scenarios, YDOs are expected to
divert more individuals from prison than it introduces.
The net effect on prison places – the breach rate
132. A risk is that the number of individuals who breach a YDO is much higher or lower than
expected. This may generate a cost to the legal, prison and probation services. The Home
Office have modelled several different scenarios with differing number of individuals who
breach their YDO to account for this.
The net effect on prison places – age demographics of breaches
133. A risk is that the age demographics of individuals who receive a YDO and the age
demographics of individuals who breach a YDO are not similar to the current age
demographics of individuals who are convicted of terrorism related offences. As a result,
there could be net increases in prison places for certain age demographics. However, there
is no evidence to suggest that the age demographics are different, and there would have
to be a significant divergence for a noticeable change to occur.
Measure 1B: Terrorism and State Threat Prevention and Investigation Measures:
unapproved articles capable of being used as a weapon.
Number of TPIM/STPIMs issued
134. The main analytical risk is that the actual volume of new TPIMs/STPIMs issued per year
differs significantly from expected. This would increase/decrease the estimated number of
potential TPIM breaches and costs. There is no indication that this is the case as the
average number of TPIMs issued per year remains relatively stable. However, the figures
provided are indicative based on previous years and may not be representative of actual
volumes over the ten-year appraisal period.
The number of appeals
135. There is a risk that individuals appeal this measure which would incur a cost to the legal
system. There is no precedent of TPIM subjects appealing this type of measure. As a result,
it is assumed that there will be no appeals.

Measure 1DApplication of certain terrorism offences (wearing of uniform / displaying an
article) to conduct in prisons as well as other prescribed places of detention or residence
The number of appeals
136. It is currently assumed that no individual will appeal this offence, so the costs have not been
monetised. It is possible for an offender to appeal an offence, which would generate a cost
to the prison and legal system.

H. Annex

Mandatory specific impact test - Statutory Equalities Duties Complete
The department assesses that these measures will not be directly
discriminatory within the meaning of the Equality Act 2010 , with the exception
of the YDO which will directly discriminate on the basis of age . The YDO will
only be available to those under 21 at the time that the police make the
application to the courts.
Most of t he proposed changes may result in some indirect discrimination on
certain protected characteristics. For example, the UK’s definition of terrorism,
which terrorism offences are based on, includes the use or threat of action
where this is made for the purpose of advancing a cause, including a religious
cause. As a result, the statistics on terrorist offenders may over -represent
certain religions in comparison to the make -up of religious beliefs across the
UK.
The Department assesses that any indirect discrimination would be objectively
justified as a proportionate means of achieving the government’s legitimate aim
of protecting the public from the threat of terrorism.
The SRO has agreed these summary findings.
Yes