The Principles of Discovery
[11] Caselaw is clear and abundant. The core of discovery principles is that its scope should be wide, with relevancy construed liberally, without, however, allowing it to enter the realm of a fishing expedition. These basic principles are essential because the purpose of discovery is to enable parties to know the case they have to meet at trial, to know the facts upon which the opposing party relies, to narrow or eliminate issues, to obtain admissions that will facilitate the proof of matters in issue and, finally, to avoid surprise at trial (General Electric Capital Canada Inc. v The Queen, 2008 TCC 668, 2009 DTC 1186, at para 14). This is all with a view to making the hearing of an appeal streamlined and to ensure that the parties are focussed on the appropriate issues.
See Burlington Resources Finance Company v. The Queen 2015 TCC 71 (Campbell)