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

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25. The Régie may call witnesses and require the production of documents at the request of a participant or on its own initiative.
The Régie, where applicable, must issue a subpoena to a participant so requesting who is then responsible for serving the subpoena on the witness at the participant’s own expense.
The subpoena must be served at least 5 clear days before the date of attendance of the witness, unless the Régie issues special directions.
O.C. 437-2006, s. 25.