French Code of civil procedure

The facts on which the resolution of the dispute depends may, at the request of the parties or ex officio, be the subject of any legally permissible investigative measure.

Investigative measures may be ordered in any event, if the judge does not have sufficient evidence to rule.

If there is a legitimate reason to preserve or establish before any trial proof of facts on which the outcome of a dispute may depend, legally admissible investigative measures may be ordered at the request of any interested party, on application or in summary proceedings.

An investigative measure may only be ordered in respect of a fact if the party alleging it does not have sufficient evidence to prove it. Under no circumstances may an investigative measure be ordered to make up for the party’s failure to provide evidence.

The judge must limit the choice of measure to what is sufficient for the resolution of the dispute, endeavouring to select what is simplest and least onerous.

The judge may combine several investigative measures. He may, at any time and even during the course of the investigation, decide to combine any other necessary measure with those already ordered.

The judge may at any time increase or restrict the scope of the measures prescribed.