Article 456 Spanish Criminal Procedure Act: When Expert Evidence Must Be Ordered

Article 456 of the Criminal Procedure Act provides that the judge shall order an expert report where scientific or artistic knowledge is necessary or convenient in order to know or assess an important fact or circumstance in the investigation. The provision is the basis of every application by the defence for a forensic, ballistic, accounting, toxicological or documentary examination, and the words necessary or convenient set a low threshold. A refusal, recorded with a formal protest, is a ground of appeal under articles 790 and 850.

Wording of Article 456 of the Spanish Criminal Procedure Act

Requirements and procedure

1. An important fact or circumstance in the investigation, which the applicant must identify precisely rather than in general terms.
2. The necessity or convenience of scientific or artistic knowledge in order to know or assess that fact, which excludes matters within ordinary experience.
3. A reasoned application identifying the discipline required and the questions to be answered.
4. Relevance to the issues in the case, since an expert report on a matter that cannot affect the outcome will be refused.

Defence strategy

Framing the application. Applications are refused when they are framed generally. The application must state the fact to be established, the discipline required, the specific questions and the reason why the answer may alter the outcome. An application for a report on the mechanism of an injury, on the calibration of a breath device, on the recoverability of deleted data or on the market value of property is granted far more readily when put in those terms.

The official report is not the only evidence. Where an official body has already reported, the defence remains entitled to a further examination, and the article does not confine expert evidence to the official services. Instructing an independent expert at the investigation stage, rather than producing a report shortly before trial, gives the court time to hear both and gives the defence access to the underlying material.

Recording the refusal. A refusal must be met with a formal protest, and where possible with a written application repeating the request. Without that record, the complaint cannot be revived on appeal, since both article 790 and the grounds of cassation require that the refusal was objected to. This is the most frequent reason why an otherwise strong ground of appeal fails.

Preserving the object of the examination. Expert evidence depends on the object surviving. Vehicles are repaired, premises are altered, devices are wiped and biological samples degrade. The defence therefore applies at once for the preservation of the object as well as for the report, since a right to an examination is of no value once the object has gone.

• Article 790: appeal against judgment
• Spanish Criminal Procedure Act by article
• Article 152: bodily harm by negligence
• Spanish-language entry

This entry is provided for information only and does not constitute legal advice. The application of any provision depends on the circumstances of the individual case and requires examination of the case file by a qualified lawyer.