The lawyer as a witness: the legal profession considers asking a colleague to testify a serious infringement

In a highly tense lawsuit, the temptation can arise to propose the other party's lawyer, or another lawyer who took part in the negotiations, as a witness to testify about what they know. Interpretative Circular 1/2025 of the General Council of the Spanish Legal Profession, published in November 2025, addresses that situation and concludes that asking for that testimony is a serious infringement.

The starting rule

Article 11.12 of the Code of Ethics of the Spanish Legal Profession establishes that a lawyer must refrain from asking for the witness testimony of another lawyer on facts related to their professional activity.

The circular links that rule to others:

• General Statute of the Spanish Legal Profession, Article 59.2.e): the lawyer must not ask for the testimony of the opposing party's lawyer or of other lawyers who took part in the matter.
• General Statute, Article 125.a) vii: calling a lawyer as a witness on facts from their professional activity is a serious infringement.
• General Statute, Article 124.f): breach of professional secrecy is a very serious infringement.
• Organic Law of the Judiciary, Article 542.3: lawyers must keep secret the facts they learn through their professional work and cannot be compelled to testify about them.
• Organic Law 5/2024, on the Right of Defence, Article 16: exempts lawyers from testifying on facts, documents or information obtained in their professional activity.

The circular also notes that Article 371 of the Civil Procedure Act applies to lawyers only in a supplementary way, because their regime is that of Article 542.3 of the Organic Law of the Judiciary.

Why it is an infringement

Professional secrecy protects the relationship of trust between lawyer and client, and also communications between lawyers. Asking a colleague to testify about their work puts that lawyer in an impossible choice: testify and breach secrecy, or refuse and face the proceedings.

The General Statute reinforces that protection. Its Article 21 includes in confidentiality the duty and right to keep secrets and not to be compelled to testify. Its Article 23 prevents submitting or passing on correspondence with the opposing lawyer without authorisation. And its Article 58 protects the lawyer's freedom and independence: if a judge seeks to compel them to testify, they can ask for the protection of their bar association's Governing Board.

The circular's conclusions

1. Asking for a lawyer's testimony on professional matters is a serious infringement.
2. It is an infringement of mere conduct: no external result needs to occur.
3. It is complete when it is clear that testimony was requested on matters protected by professional secrecy.
4. When setting the penalty, whether the testimony was actually given must be weighed. Article 123 of the General Statute requires penalties to be proportionate to the gravity, taking into account repeat offending and the harm caused.

The circular also recalls that, under Article 11 of the Organic Law of the Judiciary, evidence obtained in violation of fundamental rights has no effect.

What to do in practice

If you are the one proposing the evidence

Before proposing a lawyer as a witness, check whether the facts they would testify about come from their professional activity. If so, the proposal can have disciplinary consequences, as well as procedural ones.

If you are the lawyer called

• Remember that the law exempts you from testifying on facts learned in your professional activity.
• If someone tries to compel you, you can ask for the protection of your bar association's Governing Board.
• Inform your client of the situation.

One more piece of professional secrecy

The circular adds to other recent interpretations by the legal profession on the scope of secrecy. One of them, Circular 1/2026, extends it to reports delivered to the client, as we analyse in our editorial on professional secrecy and reports delivered to the client. The general legal framework is in the Organic Law on the Right of Defence.

The role of bar associations in interpreting and applying the Code is one of that law's institutional guarantees. We follow their activity in Industry news.