This evidence review draws on the statutory text of the Offender Management Act 2007 (sections 28–30), the Ministry of Justice evaluation by Gannon et al. (2012; 2014), the MoJ counter-terrorism process evaluation by Keeton et al. (2023), the MoJ mandatory-polygraph factsheet (2020), and the HMPPS Polygraph Examinations Policy Framework (re-issued 2026). Full citations appear in the Sources list below.
Key takeaways
- Sections 28–30 of the Offender Management Act 2007 provide the statutory basis for mandatory polygraph testing of sexual, domestic-abuse, and terrorist offenders released on licence in England and Wales, while explicitly prohibiting the use of polygraph statements or physiological reactions as evidence in criminal proceedings.[1]
- The mandatory PCSOT pilot (2009–2012) found that 76.5% of polygraph-group offenders made at least one disclosure compared with 51.2% in the comparison group, with a mean of 2.60 versus 1.25 disclosures per offender.[2]
- Since the national rollout on 6 January 2014, over 7,000 PCSOT tests have been conducted, with two-thirds producing significant disclosures.[3]
- The counter-terrorism polygraph process evaluation (2021–2023) reported 88 examinations across 39 individuals, a 35% significant-response rate, a 72% risk-disclosure rate, and three recalls linked to disclosures.[4]
- No published UK randomised controlled trial has assessed whether the programme reduces reoffending, and cost-effectiveness data remain limited to the 2012 estimate of £556 per additional clinically significant disclosure.[5]
The statutory text: sections 28–30
The Offender Management Act 2007 (OMA 2007) introduced the first statutory framework for mandatory polygraph testing of offenders in England and Wales. Three sections are central.
Section 28 — Scope
Section 28 enables the Secretary of State to include a polygraph condition in the licence of a person serving a relevant custodial sentence for a relevant sexual offence, a relevant offence involving domestic abuse, or a relevant terrorist offence, who is released on licence and is not aged under 18 on release.[6] A “relevant custodial sentence” means a life sentence within the meaning of Chapter 2 of Part 2 of the Crime (Sentences) Act 1997, or a fixed-term sentence of not less than twelve months.[7] “Relevant sexual offence” is defined by reference to Schedule 3 to the Sexual Offences Act 2003 and related schedules.[8]
Section 29 — Effect of the polygraph condition
Section 29 defines a polygraph condition as one requiring the released person to participate in polygraph sessions conducted with a view to (a) monitoring compliance with the other conditions of the licence, or (b) improving the way in which the person is managed during release on licence.[9] Sessions must use Secretary of State-approved equipment, must be scheduled by an appropriate officer (a probation service officer following Secretary of State guidance), and the Secretary of State may make rules — via statutory instrument subject to parliamentary annulment — governing session conduct, operator qualifications, record-keeping, and reporting.[10]
Section 30 — Use in criminal proceedings
Section 30 provides an express statutory prohibition: evidence of (a) any statement made by the released person while participating in a polygraph session, and (b) any physiological reactions of the released person while being questioned in the course of a polygraph examination, may not be used in any proceedings against that person for an offence.[11]
Chronology of the programme
Offender Management Act 2007 receives Royal Assent, creating statutory power for mandatory polygraph testing of offenders on licence (ss.28–30).[6]
Mandatory polygraph pilot launches in the East and West Midlands probation regions for adult sexual offenders released on licence from sentences of 12 months or more.[12]
MoJ publishes Gannon et al., The Evaluation of the Mandatory Polygraph Pilot (Research Series 14/12).[13]
Gannon et al. peer-reviewed journal article published in Sexual Abuse 26(2):178–203.[14]
National rollout of mandatory polygraph testing for individuals convicted of sexual offences and released on licence in England and Wales.[15]
Ministry of Justice news release: Compulsory lie detector tests for serious sex offenders.[16]
Domestic Abuse Act 2021 (s.76) extends OMA 2007 polygraph condition to domestic-abuse perpetrators on licence.[17]
Counter-terrorism polygraph examinations commence under the Counter-Terrorism and Sentencing Act 2021 extension of OMA 2007.[18]
MoJ publishes Keeton et al. process evaluation of counter-terrorism polygraph examinations.[19]
HMPPS re-issues the Polygraph Examinations Policy Framework.[20]
What the PCSOT evaluations show
The principal published evidence base for the PCSOT programme comprises the MoJ-commissioned evaluation by Gannon et al. (2012) and the subsequent peer-reviewed journal article (Gannon et al., 2014). Both report data from the mandatory pilot that ran in the East and West Midlands from April 2009.
Headline findings — Gannon et al. (2012; 2014)
- 76.5% of offenders in the polygraph group made at least one disclosure, compared with 51.2% in the comparison group.[2]
- The mean number of total disclosures per offender was 2.60 in the polygraph group compared with 1.25 in the comparison group.[2]
- Approximately one third of offenders — most notably those who were higher in risk — failed their first test with a “Deception Indicated” result.[21]
- Following a clinically significant disclosure, a higher proportion of offender managers in the polygraph group than in the comparison group took supervisory actions including increasing supervision or controls (including recall), informing a third party, changing supervision focus, informing MAPP meeting or processes, or issuing a warning.[22]
- The cost of each additional clinically significant disclosure associated with the mandatory polygraph pilot was £556.[5]
| Metric | Polygraph group | Comparison group | Source |
|---|---|---|---|
| Proportion making ≥1 disclosure | 76.5% | 51.2% | Gannon et al. (2014)[2] |
| Mean disclosures per offender | 2.60 | 1.25 | Gannon et al. (2014)[2] |
| Cost per additional CSD | £556 | Gannon et al. (2012)[5] | |
| First-test “Deception Indicated” rate | ~⅓ of offenders (higher-risk predominating) | Gannon et al. (2014)[21] | |
What the counter-terrorism evaluation shows
The Counter-Terrorism and Sentencing Act 2021 extended the OMA 2007 polygraph condition to terrorist offenders. The first published process evaluation was produced by Keeton, Gerasimov, and Pearce (2023) for the Ministry of Justice, covering the period from 29 June 2021 to 30 June 2023.[4]
CT cohort in numbers
- 46 individuals subject to the polygraph licence condition.[23]
- 88 polygraph examinations completed by 39 of those individuals.[24]
- 31 examinations (35%) classified as a significant response.[25]
- 63 examinations (72%) produced disclosures of risk-related information.[26]
- 3 individuals recalled following disclosures; 1 further individual recalled in part due to polygraph non-compliance.[27]
Keeton et al. also noted that polygraph examiners working within the counter-terrorism programme had been trained and accredited to the standards set by the American Polygraph Association (APA).[28]
| Metric | PCSOT (national, to ~2020) | CT (June 2021 – June 2023) | Source |
|---|---|---|---|
| Examinations conducted | Over 7,000 | 88 | MoJ Factsheet (2020)[3]; Keeton et al. (2023)[24] |
| Significant-disclosure / significant-response rate | ~67% (two-thirds) | 35% | MoJ Factsheet (2020)[3]; Keeton et al. (2023)[25] |
| Risk-disclosure rate | Not separately reported | 72% | Keeton et al. (2023)[26] |
| Recalls linked to polygraph | Not separately reported | 3 (plus 1 compliance-related) | Keeton et al. (2023)[27] |
Comparability note. The “significant disclosure” metric in the PCSOT national statistics and the “significant response” metric in the Keeton et al. CT evaluation are not directly comparable. The PCSOT figure reported by the MoJ factsheet refers to tests “resulting in significant disclosures”, whereas Keeton et al. report a “significant response” classification (35%) alongside a distinct “risk-related disclosure” rate (72%). Readers should exercise caution when placing these figures side by side.
Cumulative operational statistics
The MoJ’s mandatory-polygraph factsheet, published alongside the Domestic Abuse Bill 2020, reported that since 6 January 2014 mandatory polygraph testing had been used with high-risk adult sexual offenders on licence, and that over 7,000 tests had taken place with individuals convicted of sexual offences, with two-thirds of those tests resulting in significant disclosures.[3]
The factsheet also confirmed two key safeguards: information from the polygraph cannot be used in criminal courts as evidence against the individual who is subject to testing, and people on supervision subject to a polygraph testing licence condition cannot be recalled to custody solely on the basis of returning a significant response.[29]
The recall rule
The HMPPS Polygraph Examinations Policy Framework (re-issued 8 January 2026) provides the operational policy position on recall:
“The policy position is that the result of a polygraph examination cannot be used as the basis of recall. However, information gathered from any part of the polygraph session may be passed onto the police or other relevant agencies, where a legal gateway permits. Additionally, any disclosures made by the person on probation during the polygraph process, that suggest the individual can no longer be safely managed in the community can be used as the basis for recall.”[30]
The Framework also requires that information from the polygraph examination be shared with partners under MAPPA or other appropriate information-sharing arrangements, citing section 14 of the Offender Management Act 2007 as a legal gateway.[31]
Evidence gaps
Whilst the published evaluations provide substantial evidence on the disclosure-facilitating effects of the programme, several important gaps remain in the published evidence base.
No published UK randomised controlled trial on recidivism. Neither the Gannon et al. evaluations (2012; 2014) nor any subsequent MoJ or HMPPS publication reports a randomised controlled trial assessing whether mandatory polygraph testing reduces reconviction or reoffending rates. The evidence base as published is limited to disclosure and supervisory-action outcomes.
Limited cost-effectiveness data. The only published cost-effectiveness figure is the £556-per-additional-CSD estimate from the 2012 Gannon et al. evaluation.[5] No subsequent cost-effectiveness analysis of the national programme has been identified in the published literature.
No published inter-rater reliability audit. No published study reports an inter-rater reliability audit of the HMPPS Polygraph Unit’s scoring decisions.
No published disaggregation by offence subtype within PCSOT. The published PCSOT evaluations do not disaggregate disclosure or examination-outcome data by offence subtype (e.g., contact versus non-contact sexual offences, intra-familial versus extra-familial).
Small CT sample. The counter-terrorism evaluation is based on 46 individuals and 88 examinations over two years, which is a small sample from which to draw generalisable conclusions about programme effectiveness for terrorist offenders.[4]
Practitioners and policy-makers seeking to develop the evidence base further may wish to consult the Standards of Practice published by the British Polygraph Society, which address quality-assurance principles relevant to programme evaluation.
Glossary
- OMA
- Offender Management Act 2007 — the primary statute enabling mandatory polygraph testing of offenders on licence in England and Wales.
- DAA
- Domestic Abuse Act 2021 — legislation that, among other provisions, extended the OMA 2007 polygraph condition to domestic-abuse perpetrators released on licence.
- CTSA
- Counter-Terrorism and Sentencing Act 2021 — legislation that extended the OMA 2007 polygraph condition to terrorist offenders released on licence.
- HMPPS
- His Majesty’s Prison and Probation Service — the executive agency of the Ministry of Justice responsible for correctional services in England and Wales, including administration of the statutory polygraph programme.
- MAPPA
- Multi-Agency Public Protection Arrangements — statutory arrangements for the assessment and management of sexual and violent offenders, under which polygraph information may be shared.
- MAPP
- Multi-Agency Public Protection — the process or meetings held under MAPPA at which risk-management decisions are taken.
- PCSOT
- Post-Conviction Sex Offender Testing — a polygraph testing programme applied to individuals convicted of sexual offences and released into the community, designed to monitor licence compliance and elicit risk-related disclosures.
- CSD
- Clinically Significant Disclosure — a disclosure made during the polygraph process that is judged to be relevant to risk management or licence compliance, and which may prompt supervisory action.
- APA
- American Polygraph Association — the largest professional body for polygraph examiners, whose standards are referenced in UK examiner training and accreditation.
- BPS
- British Polygraph Society — an unincorporated UK membership body for polygraph professionals, founded in 2017.
- CQT
- Comparison Question Test (also known as Control Question Test) — a polygraph testing format in which physiological responses to relevant questions are compared with responses to comparison questions.
- PCoSO
- Post-conviction sexual offender — an individual who has been convicted of a sexual offence and is subject to community supervision, potentially including a polygraph licence condition.
Sources
- Offender Management Act 2007, section 28 (as amended). legislation.gov.uk. https://www.legislation.gov.uk/ukpga/2007/21/section/28
- Offender Management Act 2007, section 29. legislation.gov.uk. https://www.legislation.gov.uk/ukpga/2007/21/section/29
- Offender Management Act 2007, section 30. legislation.gov.uk. https://www.legislation.gov.uk/ukpga/2007/21/section/30
- Gannon TA, Wood JL, Pina A, Vasquez E, Fraser I. The evaluation of the mandatory polygraph pilot. Ministry of Justice Research Series 14/12. London: Ministry of Justice, July 2012. https://www.gov.uk/government/publications/the-evaluation-of-the-mandatory-polygraph-pilot
- Gannon TA, Wood JL, Pina A, Tyler N, Barnoux MFL, Vasquez EA. An evaluation of mandatory polygraph testing for sexual offenders in the United Kingdom. Sexual Abuse. 2014;26(2):178–203. https://kar.kent.ac.uk/35131/
- Keeton S, Gerasimov W, Pearce L. The use and operation of counter-terrorism polygraph examinations: Process evaluation findings. Ministry of Justice Analytical Series. October 2023. https://assets.publishing.service.gov.uk/media/652d3ed0d86b1b000d3a4fdc/use-operation-counter-terrorism-polygraph-examination.pdf
- Home Office / Ministry of Justice. Domestic Abuse Bill 2020 Factsheets: Mandatory polygraph tests factsheet. GOV.UK. https://www.gov.uk/government/publications/domestic-abuse-bill-2020-factsheets/mandatory-polygraph-tests-factsheet
- HM Prison and Probation Service. Polygraph Examinations Policy Framework. Re-issue date 8 January 2026. https://assets.publishing.service.gov.uk/media/695e66418ab0677c14afdfd0/polygraph-examinations-pf.pdf
- Ministry of Justice. Compulsory lie detector tests for serious sex offenders (news release). 27 May 2014. https://www.gov.uk/government/news/compulsary-lie-detector-tests-for-serious-sex-offenders
This post is a research summary produced by the British Polygraph Society for informational purposes. It does not constitute legal advice, clinical guidance, or an endorsement of any particular testing methodology. The statutory polygraph programme in England and Wales is administered by HMPPS; the BPS has no role in that regime. Readers requiring legal or operational guidance should consult the relevant statutory instruments and HMPPS policy documents, or seek independent professional advice.