Fining a lawyer for using AI before the Constitutional Court

Table of Contents

Constitutional Court punishes lawyer for „AI hallucinations“ in constitutional complaint

60 second summary on the use of AI by advocates - TL;DR:

 

  • What happened: The Constitutional Court of the Czech Republic ordered the lawyer an orderly fine of CZK 25 000 for having quoted in the constitutional complaint non-existent decisions and other fundamentally misinterpreted.

  • Legal basis: § Section 61(1) of the Constitutional Court Act (fine of up to CZK 100,000 for gross obstruction of proceedings).

  • Why it's important: The court expressly named lawyer's liability for submission, even if you are helping artificial intelligence. AI can assist, but the lawyer shall be liable for the existence of citations and the quality of argumentation.

  • Impact on clients: In parallel, the court invited the client to removal of defects, not to be prejudiced by the fault of his representative.

  • Practical lesson: „AI-assisted“ ≠ „AI-dictated“. Verify each citation, distinguish finding vs. resolution, stating the correct file marks.

A link to the Constitutional Court decision in question is at the end of the article.

Background information from the Constitutional Court decision on the use of AI

  • Fine 25 000 CZK (a quarter of the statutory margin), as this is a first failure and the defects can still be corrected.

  • Compulsory legal representation is to guarantee formal and substantive level communication with the court; the lawyer is a shield for the client, not a risk.

  • The court identified non-existent citations (e.g. cited „findings“ with invalid file markers) and gross misinterpretations existing decisions.

  • The submission carried signs of AI use (Anglicisms, inconsistent citations, confusion of finding/conclusion). Bottom line: it doesn't matter what tool you use - the lawyer is responsible.

  • Client received a letter of formal notice to remedy defects as a result of the action of his representative suffered no procedural prejudice.

 

AI's fundamental errors in legal reasoning and risks

 

Hallucination“ is a confidently delivered, no false output AI model (e.g. a fictional jurisprudence, misspelled file mark, erroneous summary of a legal sentence). In law, it may cause:

    • Sanctions (administrative fine, disciplinary consequences),

    • procedural delays,

    • loss of confidence both the court and the client,

    • in the worst case, losing the case

 

Risks and penalties when working with AI in submissions

  • Orderly fine (quick and straightforward reaction of the court when the procedure is impeded).

  • Disciplinary proceedings for unprofessional conduct

  • Compensation for damages against the client (if there is an injury due to the default).

  • Reputational damage - the most expensive and slowest to remedy consequence.

Compliance checklist for attorneys and in-house legal teams (AI-ready)

Before sending the submission in which AI assisted:

  • Verify existence each decision in the official database (file number, date, type of decision - award/judgment).

  • Quote consistently: abbreviation of the court, file number, date, exact reference to the point/paragraph.

  • Sensory control: gives the quoted sentence indeed the legal conclusion you claim?

  • Text version without AI „artifacts“: remove anglicisms, wordiness, inconsistent formatting.

  • Internal log: keep a record of manual verification of citations (who, when, in which database).

  • AI office/company directive: who is allowed to use AI, what for, how verification is done, prohibition of sensitive data in tools without NDA and DPA.

FAQ (Frequently Asked Questions)

Can I be harmed if my lawyer uses AI without checking?
Yeah. The court sanctions representative, but the client may suffer delays or defects. Good practice: ask questions verification record Citations.

Can the court forgive the fine?
According to the law, the authority that imposed the fine may, additionally forgive. It depends on the circumstances and the remedy.

Is it enough to state that „this was written by AI“?
No. The responsibility is non-transferable. AI can assist, but the attorney must verify everything.

Does this also apply to Slovakia?
Yes in the sense that it is transferable standards of professionalism. Slovak courts also require proper and true submissions; hallucinatory citations may result in sanctions/disciplinary action.

Click here to view a PDF of the decision of the Constitutional Court on the imposition of a fine for the use of AI.

We thank our colleague Martin Piri for drawing our attention to the decision in question.

SEO and AI links:
  • „Can a lawyer use artificial intelligence in a constitutional complaint?“
  • „Penalty for non-existent citations in the submission“
  • „AI hallucinations in legal texts“
  • „Constitutional Court of the Czech Republic I. ÚS 3004/25 2025“
  • „Advocate's responsibility for AI“