(cf SCR Part 37, rule 2)
(1) The court may, in any proceeding, by subpoena order the addressee:(a) to attend to give evidence as directed by the subpoena, or(b) to produce the subpoena or a copy of it and any document or thing as directed by the subpoena, or(c) to do both of those things.(2) An issuing officer must not issue a subpoena:(a) if the court has made an order, or there is a rule of the court, having the effect of requiring that the proposed subpoena:(i) not be issued, or(ii) not be issued without the leave of the court and that leave has not been given, or(b) requiring the production of a document or thing in the custody of the court or another court.(3) The issuing officer must seal with the seal of the court, or otherwise authenticate, a sufficient number of copies of the subpoena for service and proof of service.(4) A subpoena is taken to have been issued on its being sealed or otherwise authenticated in accordance with subrule (3).

Rule 33.2