I mean, as opposed to merely cross-examining them in the course of the opposing side’s presentation of their case.
A closely related question asks of calling the defendant itself, though not its witnesses.
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Any party may call a witness that has relevant evidence (Rules 53.01 & 53.04). There is "no property in a witness" (see also Unifirst Canada Ltd. c. 9766065 Canada inc., 2021 QCCQ 7946 at para. 10). The adverse party may be called as a witness unless they've already testified or counsel has undertaken to have them appear as a witness in their case (Rule 53.07).
Clarence Darrow took the unusual step of calling the prosecution counsel as a witness during the Scopes Trial.