What Are Affirmative Defenses in Civil Litigation? Examples, Strategy, and Mistakes to Avoid

Facing a lawsuit doesn’t mean all hope is lost. In both California and federal courts, you may have powerful legal tools called affirmative defenses. These aren’t just denials—they’re arguments that even if the main facts are true, the law says you shouldn’t be held responsible.

What Is an Affirmative Defense?

An affirmative defense must be raised in your first answer to the complaint or any other claim, or you risk losing it forever. Rather than simply denying allegations, you’re telling the court there’s a reason—based on law or equity—why the plaintiff, counterclaimant, or cross-complainant shouldn’t win. For both California and federal courts, statutes require these defenses to be clearly stated (Fed. R. Civ. P. 8(c); Cal. Civ. Proc. Code § 431.30(b)).

Examples and Application

Consider a breach of contract lawsuit. You might claim as affirmative defenses that the statute of limitations expired (the plaintiff waited too long to sue), the contract was void because of fraud or duress, payment was already made, the obligation was impossible to perform, or the plaintiff themselves acted wrongly (“unclean hands” or waiver). Other common examples include estoppel (the plaintiff changed their position), lack of capacity, mutual mistake, and failure to mitigate damages.

These defenses must be supported by facts in your answer—not simply listed by name. California and federal courts alike reject “boilerplate” lists of defenses without specifics. Always tailor your factual allegations to your case.

Strategy and Pleading

To safeguard your rights, review all available defenses with a legal checklist. Raise any reasonable defense you believe may apply to your circumstances. Courts allow you to amend your answer later—but some procedural defenses (like improper service or lack of jurisdiction) must be asserted from the outset.

If you become aware of new facts after answering, request permission to add new defenses promptly. Good pleading means stating enough facts to support each defense, not repeating bare legal terms.

State vs. Federal: Key Differences

Federal judges often scrutinize affirmative defenses closely, striking those that lack factual support or that are copied without explanation. California courts similarly encourage plaintiffs to move to strike or demur to “boilerplate” affirmative defenses that lack any factual substance. In both places, thoughtful and fact-driven allegations increase credibility and reduce risk of early dismissal.

Mistakes to Avoid

Many litigants lose strong defenses by failing to plead them in the answer, relying only on denials, or by listing every possible theory with no factual explanation. Missing defenses can mean losing the ability to argue them later, while poorly pleaded defenses can be struck by motion and may draw judicial frustration.

Final Thoughts

Affirmative defenses are sometimes the key difference between losing and winning a lawsuit. Carefully review the facts and law before answering; draft clear, specific defenses based on what happened in your case. Use sample forms and pattern instructions where available, but always adapt them to your actual situation. When the stakes are high or facts are complex, it’s wise to seek guidance from a qualified litigation attorney (like myself).