Author: Sean S. Smyth KC

At its core, impeachment is a cross-examination tool that is meant to assist the adjudicator to discharge the fact-finding function and decide between competing versions of events. There are methods to be followed when impeaching a witness and legal and ethical restrictions on when and how a witness can be impeached. Instead of affecting the witness’s credibility, nothing is more effective at discrediting counsel’s credibility as attempting to impeach and failing to do so or attempting to do so in a manner that offends the rules or restrictions. This paper explores credibility and reliability, forms of impeachment, and limits on impeachment.

These materials are part of a collection presented at LESA’s Evidence Refresher program in Edmonton on April 23, 2026.