Discovery - General. Canada v. Thompson
In Canada v. Thompson (Fed CA, 2022) the Federal Court of Appeal considered when a question is relevant for the purposes of discovery:
 In Canada v. Lehigh Cement Limited, 2011 FCA 120, this Court determined that a question is relevant for discovery purposes if the answer might assist the asking party in advancing its case or damage the case of the other party:. Canada v. CHR Investment Corporation
34 The jurisprudence establishes that a question is relevant when there is a reasonable likelihood that it might elicit information which may directly or indirectly enable the party seeking the answer to advance its case or to damage the case of its adversary, or which fairly might lead to a train of inquiry that may either advance the questioning party's case or damage the case of its adversary. Whether this test is met will depend on the allegations the questioning party seeks to establish or refute…. This principle was reiterated in Madison Pacific Properties Inc. v. Canada, 2019 FCA 19, at paragraph 23.
In Canada v. CHR Investment Corporation (Fed CA, 2021) the Federal Court of Appeal considered principles of discovery under the Federal Rules, here in a tax context [paras 14-42].
. Imperial Oil v Jacques
In the Quebec case, Imperial Oil v Jacques (SCC, 2014), the Supreme Court of Canada held that investigative evidence obtained by the Crown (here the Competition Bureau) for use in criminal proceedings was not by it's nature immune from third party civil discovery procedures, though adequate protections had to be ordered to ensure that it remained confidential amongst the counsel of the civil parties. While the court speaks broadly of the public interest principles underpinning it's decision, and accepts that the Criminal Code allows such disclosure, the case must still be reviewed carefully for it's application under other provincial civil disclosure regimes.