Home Office backs audit on primate research severity
If you’ve ever wondered how the UK checks the level of suffering in animal research, today’s update matters. The Home Office has published an exchange of letters confirming that Lord Hanson of Flint, a minister at the department, has accepted advice to review how “severity” is assessed in certain primate studies. The correspondence was released on 28 October 2025.
The advice came from Dr Sally Robinson, Chair of the Animals in Science Committee (ASC). Writing on 18 August 2025, she recommended a themed audit to check how project licence holders decide the “actual” severity after work is done, and how they consider cumulative severity in licences that may involve severe procedures on non‑human primates. She also suggested the audit could support better guidance and sharing of good practice.
Lord Hanson replied on 1 October 2025 to say he accepts the recommendation. He noted that the Animals in Science Regulation Unit (ASRU) is finishing a regulatory reform programme and, subject to the Regulator’s scheduling, he expects the audits to begin in 2026. The Home Office then published both letters on 28 October 2025 so the public can see the decision.
Quick explainer: a project licence authorises a programme of work, including the species, numbers and procedures allowed. Each licence starts with a “prospective” severity category (what is expected), and ends with an “actual” severity recording (what animals actually experienced). Cumulative severity looks at the overall experience when animals undergo more than one procedure over time, so a string of moderate experiences might add up to something closer to severe. This is the part the audit will examine for primate projects flagged as potentially severe.
Who does what? ASRU runs the licensing system and enforces the Animals (Scientific Procedures) Act 1986. Inside research institutions, the Animal Welfare and Ethical Review Body (AWERB) must carry out retrospective assessments and send conclusions to the Home Office. The ASC, an independent expert committee, advises ministers on sensitive applications, including projects seeking authority for severe procedures in non‑human primates.
Why primate work is tightly controlled: UK law sets extra conditions before primate research can be licensed. Applicants must show there is no suitable alternative and meet strict tests on purpose and justification; great apes are not permitted. These rules sit alongside the long‑standing requirement to replace, reduce and refine the use of animals wherever possible.
What changes now? This is not new law. It is a commitment to a targeted audit of how severity is recorded and judged in a specific slice of primate research. The audit’s purpose is quality assurance: to understand current practice, check consistency, and, if needed, shape clearer guidance for licence holders and inspectors. Ministers expect ASRU to set the timetable, with work starting during 2026.
If you study or work in this area, the message is practical. Keep your severity assessment methods clear and well‑documented, make sure AWERB reviews are timely and thorough, and ensure non‑technical summaries explain plainly what animals experience and why alternatives were not possible. These are already expectations in guidance and will be in focus during the audit.
A note on people: Lord Hanson of Flint is a Minister of State at the Home Office and serves as the department’s Lords minister. He was appointed in July 2024 after being created a life peer the same month, and his portfolio includes taking Home Office business through the House of Lords.
What to watch next: look for ASRU confirmation of the audit start date in 2026 and, later, for any updated guidance on how cumulative severity should be considered and reported in primate projects. We’ll keep tracking this so you can see how oversight evolves and what it means for future licence applications.