Cross-Examination
Cross-examination is the questioning of a witness by the party who did not call them. In a criminal trial, the Crown calls a witness and conducts examination-in-chief; the defence then cross-examines. Cross-examination is the central engine of adversarial trial process — it tests the witness's evidence for accuracy, completeness, bias, and reliability. The right to cross-examine is a fundamental aspect of the right to make full answer and defence under section 7 of the Charter.
Mass Tsang's criminal lawyers approach cross-examination as the heart of trial preparation. For more on Canadian evidence rules, see our blog post on evidence in criminal trials.
What cross-examination accomplishes
Effective cross-examination can: expose inconsistencies between the witness's testimony and prior statements; reveal bias, motive to fabricate, or relationship to the parties; test perception, memory, and observation; pin down details that constrain later argument; elicit favourable evidence the witness was not asked about in chief; and undermine the witness's credibility where appropriate. Cross-examination is conducted under different rules from examination-in-chief — leading questions are permitted, and the questioning is generally adversarial.
Limits on cross-examination
Cross-examination is not unlimited. Counsel cannot ask questions that are: irrelevant; unduly oppressive or harassing; designed solely to embarrass; based on misrepresentation of prior evidence; or — in sexual offence cases — barred by section 276 (the "rape shield" provisions limiting cross-examination on sexual history) or the Mills regime (governing access to third-party records). Counsel must also have a good-faith basis for any factual premise put to a witness.
Cross-examination of the accused
If the accused testifies, they are subject to cross-examination like any other witness — with one important limit: section 5 of the Canada Evidence Act provides protection against cross-examination on prior criminal record for the purpose of demonstrating propensity, though the record can sometimes be used to attack credibility under section 12. The decision whether the accused should testify is one of the most important strategic calls in any trial.
Preparation
Effective cross-examination requires intensive preparation — thorough disclosure review, mastery of the witness's prior statements, knowledge of the case theory, and a clear sense of what each line of questioning is intended to achieve. A poorly prepared cross-examination can entrench the witness's evidence rather than undermine it.
Related glossary terms
