About this guidance

This guidance provides a set of standards and definitions to be used with MoJ statistical outputs. While its primary focus is on National Statistics, producers of other statistics, data and MI are recommended to follow the same standards.

Guidance is developed and overseen by the MoJ Harmonisation Group, which contains representatives from across a range of statistical teams within MoJ.


The MoJ Harmonisation Group works alongside the GSS Harmonisation Champions Network which co-ordinates data standardisation and harmonisation across the GSS to assist with the delivery of the GSS Harmonisation Strategy

Harmonisation is the process by which data producers aim to:

  • use the same definitions
  • use the same survey questions
  • use administrative data in the same way
  • present data in the same way

You can read more about Harmonisation on the GSS Guidance page

The GSS also produce a set of Harmonised Principles, many of which are included in this guidance.

How to use this guidance

This guidance is mainly intended as a guide for producing machine-readable, open datasets to be published alongside statistical outputs. All producers are encouraged to produce such datasets as a way to make their data more accessible to users.

Producers should also consult this guidance when producing statistical tables and commentary to ensure they are using terminology consistently. Where there are particular considerations relevant to statistical reporting, these are included in sections entitled ‘Reporting Guidance’.

This guidance is intended to act as a supplement to the GSS Harmonised Principles. Producers should also consult these and use both in conjunction. There are some cases where this guidance will differ from the GSS Principles. In these cases, any differences are explained and the MoJ Guidance should generally be used as any adjustments have been made to take into account MoJ requirements.