The Bar Standards Board has introduced important additions to its Handbook (Version 4.9), effective from 5 May 2026, providing further guidance to barristers on disclosure obligations and the proper handling of expert evidence.

In a new briefing note, Philip Stott and Charlotte Gamble examine the latest amendments and consider their significance for practitioners across criminal and regulatory law.

The changes include:

• New guidance emphasising barristers' responsibilities in relation to disclosure obligations, including compliance with the Criminal Procedure and Investigation Act 1996 regime and the Attorney General's Guidelines on Disclosure.
• Clarification that those acting for the prosecution must remain mindful of continuing disclosure duties, including where material comes to light after proceedings have concluded that may cast doubt on the safety of a conviction.
• New guidance concerning expert evidence, requiring barristers to ensure that expert witnesses understand their duties to the court and that the independence and objectivity of expert evidence is maintained.

The briefing explores the background to these developments, including issues highlighted by the Post Office Horizon IT Inquiry, and considers how the new guidance may affect barristers' professional obligations in practice.

Read the full briefing note here. 

For further information on professional regulation, criminal law or regulatory matters, please contact our clerking team at barristers@qebhw.co.uk.