What Works Tool
Published 29 January 2026
Applies to England and Wales
© Crown copyright 2026
This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: psi@nationalarchives.gov.uk.
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This publication is available at https://www.gov.uk/government/statistics/justice-data-lab-statistics-january-2026/what-works-tool
1. Introduction
The What Works Tool is a visual presentation of the results of the analyses conducted by the Justice Data Lab (JDL) from 2013 to present.
The tool has been developed to provide a quick and easy to use overview of JDL evaluations. It is updated and published alongside new evaluations.
Users can:
- observe the summary statistics of all JDL analyses
- group and filter all JDL analyses by different categories
- view summary statistics in graph and table format
- view the data behind the tool
- find a link to all JDL reports included in the tool
2. What Works Tool
Click on the link below to access the What Works Tool.
Justice Data Lab What Works Tool, January 2026
Users are encouraged to use this tool alongside JDL evaluation reports, User Guidance and Methodology Paper to ensure correct understanding of the data.
The tool also provides instructions, a glossary of terms and useful links.
3. How to send us your feedback
We welcome any comments or feedback about the tool, including your views on how the tool can be improved. Enquiries and feedback should be directed to:
Justice Data Lab team