R-6.01, r. 4 - Rules respecting the procedure of the Régie de l’énergie

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30. A challenge to a request for recognition of status as an expert witness or consultant must be made in writing.
In the case of a consultant, the challenge must be made within 5 working days of the date on which the request for recognition is received.
In the case of an expert witness, the challenge must be made within a reasonable time before the testimony of the expert witness, and the Régie must dispose of the challenge at the hearing.
O.C. 437-2006, s. 30.