Is it harder for a public figure or politician to win a defamation case in Ontario?

Not dramatically harder in terms of the basic legal test, but practically more challenging in some respects. Ontario law does not create a separate, formally higher legal standard for public figures and politicians to meet, the way some other countries' defamation laws do, so a politician generally proves the same basic elements as anyone else bringing a claim.

That said, public figures and politicians tend to face more available defences working against them in practice, since criticism and comment about their public conduct is more likely to fall within the fair comment and responsible communication defences discussed elsewhere, and courts have generally recognized that people in public life should expect closer scrutiny and more robust criticism of how they perform their public role than a private individual would. Statements about a public figure's genuinely private life, unrelated to their public role, are generally treated the same as they would be for anyone else. The practical difficulty for public figures often comes from these available defences, rather than from any formally different legal threshold applied to the claim itself.