The Protected Witness in Criminal Proceedings in Spain (2026)

The figure of the protected witness seeks a difficult balance: protecting the person who testifies from reprisals without sacrificing the defendant's right of defence. As criminal lawyers, we explain how it works.

What a Protected Witness Is

Organic Law 19/1994 on the protection of witnesses and experts in criminal cases allows protection measures to be adopted where there is a serious danger to the person, liberty or property of the witness or their relatives. It is common in drug-trafficking, organised-crime or violence cases.

The Protection Measures

• That their identity data does not appear in the proceedings.
• That they appear with their identity concealed or using a code.
• Testifying while avoiding visual identification: screen, video link or image and voice distortion.
• Police protection and, in extreme cases, a change of identity.

The Tension With the Right of Defence

The witness's anonymity hampers the defence: it prevents checking whether they have enmity, an interest or reasons to lie. The law therefore allows the defence to request the identity of the protected witness before trial, in order to challenge them effectively.

How It Is Countered

The defence can challenge the measures where they are unjustified, request the witness's identity, question them thoroughly on credibility and highlight the absence of corroborating evidence. The presumption of innocence requires solid evidence, not a single anonymous testimony.