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

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24. Unless the Régie issues directions to the contrary, a participant in an oral hearing may call and examine witnesses, examine the other participants’ witnesses and present the participant’s position.
Witnesses are heard under oath, which is a solemn affirmation to tell the truth, the whole truth and nothing but the truth.
Unless the Régie decides otherwise, a participant must file in writing, within the prescribed time, the expert testimony to be relied on in support of the participant’s position.
O.C. 437-2006, s. 24.