ChatGPT for UK solicitors: keep client and matter details out

AI for solicitors rarely means uploading the whole file. What goes into ChatGPT is a piece of it: a draft witness statement, an attendance note, a Home Office letter for a trainee to summarise, the chronology going to counsel.

The rest of the practice pastes too. Private client turns a will instruction or a lasting power of attorney into a plain-English letter. Property tidies a TR1 file note and the SDLT figures for the buyer. Employment drafts the narrative for an ET1 from a client’s three-page email. Every one of those pieces opens with the lines that lead straight back to the client: the National Insurance number, the NHS number, the date of birth, your own matter reference and the tribunal’s appeal number, with a copy of the passport from the ID check.

Immigration is where the warning came from: in [2026] UKUT 00081 (IAC), promulgated on 17 November 2025, the Upper Tribunal said in its headnote that uploading confidential documents to ChatGPT places them “in the public domain”. A witness statement or a skeleton argument going to court has rules of its own, and our guide to AI in court documents sets out what you sign.

So the real question is less which assistant the practice picks than what the passage still says when it lands. Taking the names out is only the first step, and what remains is still personal data for the firm. Our guide on cleaning a client file under the UK GDPR explains what is left and how to test it.

Solicitors can use ChatGPT on client work if the safeguards the SRA expects are in place. Taking the client’s identifiers out of the passage first is one of them, but it is not enough on its own. In the invented witness statement below, the client’s name, date of birth and NHS number are covered on the fee earner’s own machine, and the two references at the top, ours and the tribunal’s, become placeholders as well.

The assistant drafts around those placeholders, and when its answer comes back the client’s real details go back in on the same screen. The fee earner sees the passage exactly as the assistant will receive it, and can restore anything the draft genuinely needs before pressing send.

Conveyancing behaves differently, and it is worth knowing how. In a made-up TR1 file note, the seller’s name, the property address, the passport number and the driving licence number became placeholders, but the Land Registry title number stayed readable: it sits on a public register, so Nonimo leaves it alone. Delete it by hand if the assistant has no need to know which title it is.

The SRA’s AI guidance now includes a warning notice on the misuse of AI, published on 17 August 2026, and the sentence quoted here is the one a practice on a paid plan should read twice.

The notice then asks firms to understand the safeguards that apply and make sure they fit the nature and sensitivity of the information. A subscription answers only part of that. The notice also shapes your client care terms.

The contractual safeguard comes from your agreement with OpenAI or Anthropic. The technical safeguard is what happens to the passage before it is sent, and that is where Nonimo works. Client identifiers are replaced on the machine itself.

If the whole practice already works inside Microsoft Copilot, paragraph 21 of the Upper Tribunal’s decision speaks to that choice, and our guide to Copilot and confidential information goes through it. This page is for the practice where people reach for ChatGPT or Claude. Either way, paragraph 7.2 of the Code of Conduct still expects you to justify the decision.

Two texts from the bench frame how a firm should think about the chat window. The first is R (Ayinde) v London Borough of Haringey, decided by the Divisional Court with Al-Haroun v Qatar National Bank on 6 June 2025. Fictitious authorities had gone before the court in both cases, lawyers from both were referred to their regulators, and at paragraph 81, sending the solicitor in Al-Haroun to the SRA, the court put it bluntly: a lawyer is not entitled to rely on their lay client for the accuracy of citations of authority. That is about what comes out of the assistant.

The second is about what goes in. The AI guidance for judicial office holders, reissued on 31 October 2025, tells judges not to enter private or confidential information into a public AI chatbot, because anything put into one should be seen as published to all the world. It adds that disabling chat history helps, but that even with history off it should be assumed the data is being disclosed.

Judges are not solicitors, and a firm’s enterprise terms may promise more than a public chatbot does. But paragraph 6.3 of the Code of Conduct reaches the affairs of current and former clients alike, so an old matter file used as a precedent counts too. Taking the client’s identifiers out before the paste means the question of what the provider does with history never touches them.

A practice can start with a single fee earner’s machine, a Mac or a Windows PC, ideally in the team that pastes most: immigration, employment or private client.

Each machine gets its own install, and the next attendance note on the desk shows whether it suits the way that team drafts.

For every machine at once, IT sets the browser extension through group policy and it covers text going into the AI tools without being called; the practice manager arranges that through hello@nonimo.ai. Fee earners keep using ChatGPT or Claude in the browser they already have open.