What is the seatbelt defense in Florida?

Florida recognizes the seat belt defense as a form of comparative negligence, established by case law rather than statute.

What the defense must prove. That a seat belt was available and operational, that the plaintiff failed to use it, that the failure was unreasonable under the circumstances, and that it contributed to producing the injuries.

That last element carries the argument. It generally requires expert testimony — a biomechanical or accident reconstruction opinion that the injuries would have been materially less severe with a belt. Without that, the defense is an assertion.

Where it fails. Injuries that would have occurred regardless. Crashes where belt use wouldn't have changed the mechanism. Situations where the belt was defective.

How it's used in practice. Frequently as a negotiating lever rather than a litigated defense, because developing it properly is expensive. That's worth knowing — an adjuster raising it in a phone call has not necessarily developed anything.