Dear Maya and Anna

Modern slavery data

Thank for your letter of 26 October raising your concerns about the Home Office’s use and release of data and statistics on modern slavery. We have investigated the issues you raised.

Today we wrote to the Home Office’s Chief Scientific Adviser about the use of its National Referral Mechanism (NRM) statistics in the Home Office press release and Home Secretary’s speech you highlighted in your letter. We consider that the NRM statistics do not support the claims that people are “gaming” the modern slavery system, and the source of the claim is unclear to us. We have asked the Home Office to ensure that claims in public statements are clear on whether they are sourced from published statistics or from other reliable evidence, to avoid the risk of misleading people.

You raised an issue regarding the discrepancy in the Home Office’s approach to releasing information via Parliamentary Questions (PQ) and Freedom of Information (FOI) requests – where historically some data, which have not been released to answer a PQ, have later been released via FOI. In the examples you give, the Home Office did behave in line with the norms of using available public information for answering PQs. However, the Code of Practice for Statistics encourages the release of information that is in the public interest, and it is our general view that the best way to make information publicly available is to publish an ad hoc statistical release. We recognise that, because information about modern slavery and migration is held on different administrative systems, it can be challenging to extract the information needed to answer questions via PQs and FOIs within the time and cost limits. But we also consider that, in some of the examples you give, the Home Office could have been more transparent about why it could not disclose data in PQs, for example, when stating that it does not hold certain information which is later released via FOI request.

Finally, thank you for making us aware of data gaps on modern slavery. We are currently reviewing the trustworthiness, quality and value of the NRM statistics against the Code of Practice for Statistics. This includes the relevance of the statistics to users. We have discussed the data gaps with the NRM statistics team as part of that review. It is our understanding that these gaps can only be filled by linking NRM data with data from other administrative systems. We have encouraged the statistics team to explore linking NRM data with data from other sources to add further insight.

Thank you again for bringing these issues to our attention. We would be happy to discuss this further if that would be helpful.

Yours sincerely

Ed Humpherson
Director General for Regulation