Privilege Claims on Discovery in Ontario: What You Don't Have to Disclose

Discovery in an Ontario lawsuit is broad — you generally have to produce documents relevant to the dispute, even ones that hurt your case. But "broad" doesn't mean "everything." Some categories of documents can be withheld entirely, and understanding privilege on discovery is what lets you tell the difference between a document you must hand over and one you're entitled to keep back.

Getting this wrong in either direction causes problems. Over-claiming privilege can draw a costly motion and damage your credibility with the court. Under-claiming it can mean handing the other side material that should have stayed protected.

The Three Main Types of Privilege You'll See on Discovery

Most privilege claims in Ontario civil litigation fall into one of three categories:

• Solicitor-client privilege — protects confidential communications between a client and their lawyer made for the purpose of giving or getting legal advice.
• Litigation privilege — protects documents created for the dominant purpose of existing or anticipated litigation, such as a lawyer's internal notes, expert reports prepared for the case, or witness statements gathered in preparation for trial.
• Settlement privilege (without prejudice communications) — protects communications genuinely aimed at settling the dispute, so parties can negotiate candidly without those statements being used against them later if settlement fails.

Each type protects a different thing for a different reason, and a document can sometimes fall under more than one category at once.

How You Claim Privilege on Discovery

Ontario's discovery process doesn't let you simply leave a privileged document off your list and say nothing. Instead, the standard approach is:

1. Identify the document as one that exists and is relevant to the case.
2. List it in your affidavit of documents in the section reserved for privileged material — describing it generally (date, type of document, and general subject matter) without revealing its contents.
3. State the basis for the privilege claim (solicitor-client, litigation, or settlement privilege).
4. Withhold the actual document itself from production to the other side.

This approach lets the other party know a document exists and roughly what it concerns, while still protecting the substance of what makes it privileged.

What Isn't Privileged

Privilege protects the communication or the document created for that purpose — it does not protect the underlying facts. A few common examples of what typically isn't privileged:

• The facts themselves, even if you first learned them from your lawyer
• Ordinary business records created in the normal course of business, even if they later become relevant to a lawsuit
• Communications with your lawyer that weren't for the purpose of legal advice (e.g., purely administrative scheduling)
• A document that was privileged but has since been shared with someone outside the privileged relationship, which can waive the privilege

This last point trips people up often: privilege can be lost — waived — by sharing a document too broadly, even accidentally, so treat privileged material carefully from the moment it's created.

Comparing the Main Privilege Types

Challenging a Privilege Claim

If the other side thinks a privilege claim is being used too broadly — to shield documents that don't actually qualify — they can challenge it. Typically this involves bringing the dispute to the court, which can review the documents privately to decide whether the claimed privilege genuinely applies. Losing a privilege challenge can mean the document has to be produced after all, so privilege claims should be made carefully and only where they're genuinely justified, not as a reflexive way to withhold anything unfavourable.

Frequently asked questions