R v Figiola – 2018 ONCA 578 (Doherty JA):

[61] In my view, if the Crown has a good faith basis for believing that a witness has relevant evidence to give, the Crown may call that witness even though the Crown expects that the witness will give evidence
inconsistent with the Crown’s position and evidence that contradicts the witness’ prior statements. The Crown may call that witness even though it anticipates applying for leave to cross-examine that witness and
challenging the credibility of that witness in certain respects: see D. Paciocco, at pp. 358-59. In choosing to call that witness, however, the Crown must realize that the trial judge has a discretion to both prohibit and limit cross-examination of the witness. In some circumstances, the Crown may call the witness only to find itself stuck with the answers given in-chief by that witness.