A copy of the decision ordering an expert opinion is sent without delay to the public prosecutor and to the parties, who have a period of ten days in which to ask the investigating judge, in accordance with the procedures set out in the penultimate paragraph of Article 81, to amend or supplement the questions put to the expert or to add to the expert or experts already appointed an expert of their choice from one of the lists mentioned in Article 157.
If the judge does not grant the requests provided for in the first paragraph within ten days of receiving them, he shall make a reasoned order. This order or the absence of an order may be challenged within ten days before the President of the Investigating Chamber. The latter rules in a reasoned decision that is not subject to appeal.
This article shall not apply where the expert examination operations and the submission of the conclusions by the expert must take place as a matter of urgency and cannot be deferred during the ten-day period provided for in the first paragraph or where the communication provided for in the first paragraph is likely to hinder the completion of the investigations.
It is also not applicable to categories of expert reports whose conclusions have no bearing on the determination of the guilt of the person under investigation and whose list is fixed by decree.
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