Accessing the Justice Data Lab service

Information provided to organisations supporting the rehabilitation of offenders.


Data upload template

Justice Data Lab: user guidance

Methodology paper

Data protection impact assessment

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Privacy impact assessment


The Justice Data Lab gives organisations working with offenders access to central reoffending data. The service provides this information to help organisations to assess the impact of their work on reducing reoffending. It also helps develop a collaborative understanding of effective rehabilitation.

To use the service, complete the ‘data upload template’ with details of the individuals your organisation has worked with, and information about the services provided. The template must be sent by secure email (gsi or CJSM).

If the information in the ‘data upload template’ meets the minimum criteria, the Justice Data Lab will provide an analysis which assesses the impact of that programme against various reoffending measures (including the 1 year proven reoffending rate and the frequency of reoffending over the 1 year). The results will be returned in a clear and easy to understand format, with explanations of the key metrics, and any caveats and limitations needed to interpret the results.

See all results published so far at: Justice Data Lab statistics reports

In March 2016, the Justice Data Lab published a methodology review report, which was a response to a peer review of the JDL methodology that was put in place at the start of the JDL service as well as an update on how the process had developed during the pilot phase.

Update on the Justice Data Lab service – August 2017

The Justice Data Lab team has brought reoffending data up to June 2015 into the service. You can now submit information on the individuals you were working with between January and June 2015, in addition to the years 2002 to 2014. The Justice Data Lab now brings in quarterly updates to the reoffending data. If you have any questions about the latest available data email a member of the team at

Published 7 November 2014
Last updated 25 May 2018 + show all updates
  1. Documents updated to comply with GDPR.
  2. Data upload template updated.
  3. June 2016 update added to page.
  4. First published.