What happens during the discovery process in an Ontario civil lawsuit?

Discovery is a pre-trial phase in Ontario civil litigation where each party is required to disclose relevant evidence to the other side. It has two main components: documentary discovery and oral examinations.

Documentary discovery requires each party to prepare an Affidavit of Documents listing all relevant documents in their possession or control — both those they plan to rely on and those that may be adverse to their case. The opposing party then has the right to inspect and copy listed documents. A party who withholds relevant documents risks serious consequences, including cost sanctions or adverse inferences at trial.

Oral examinations for discovery allow each side to question a representative of the opposing party under oath, before a court reporter, outside the courtroom. The answers form part of the record and can be used at trial to contradict the witness or fill in facts. Both sides prepare extensively for examinations, and the questions can be very broad — relevance is the main test, not admissibility.

In smaller or simpler cases, the parties sometimes agree to limit the scope of discovery. In complex commercial litigation, discovery can take months and generate thousands of pages of documents. How thoroughly you participate in discovery often determines the strength of your trial position.