The Texas Supreme Court has finally done away with the prohibition on seat-belt evidence in auto accident cases. See Nabors Well Services, LTD. et al v. Romero, et al. I recall thinking in law school just how odd it was that a defendant couldn’t introduce evidence of plaintiff’s failure to wear his seat belt. After all, the elements of negligence are duty, breach, causation and damages. In a hypothetical case where “but for” plaintiff’s failure to wear his seat belt he probably wouldn’t have impacted the windshield thereby causing the head injury for which he brought suit, surely he breached the duty he owed himself by willfully refusing to use a readily available device that would greatly reduce the risk of smashing his head on the windshield. But that wasn’t the law.

Moving one link up the causal chain the court four decades earlier had reasoned that liability hinged upon the immediate cause of the cars’ collision rather than the cause of plaintiff’s injury. The thought was that if defendant’s car hadn’t struck plaintiff’s then the plaintiff wouldn’t have hit his head; seat belt or no. But you’re not entitled to a recovery, irrespective of defendant’s reckless driving, just because you’ve been in an accident. You have to show that defendant caused you to suffer damages. So the real question is what was the cause of plaintiff’s damages, and here the liability question ought to encompass all those acts or omissions that bear upon the question of why plaintiff hit his head on the windshield.

Another question is why start the causal inquiry either at the immediate cause of the collision or at the immediate cause of plaintiff’s head hitting the windshield? What if someone had mistakenly called plaintiff to tell him he needed to come back downtown to work when he otherwise wouldn’t? What if someone else had been texting at a red light causing the plaintiff in the car behind him to miss the light thereby 10 minutes later bringing plaintiff into the path of defendant’s vehicle (which of course wouldn’t have been there when plaintiff passed that point had me made the first light 11 minutes earlier)? Why doesn’t legal causation extend to these other “but for” causal links? Nobody has a good answer because there’s not one when courts try to base legal causation on “but for” causation alone. All they can do is pick a link or two in the causal chain and pretend not to notice, or worse yet try to explain away, all the other “but for” causal links in it.

If on the other hand you decide that risk is the better determinant of legal causation you get not only a coherent explanation of tort liability, you also get better public policy. Imagine a simple rule like: everyone who creates a substantial risk has a duty to minimize it. Driving is one of the riskiest things you can do, accounting annually for tens of thousands of deaths. As the court demonstrates with National Highway Traffic Safety Administration data you can dramatically decrease that risk by wearing your seat belt. On the other hand the risk of head trauma posed by a single commute or a missed green light ranges from negligible to infinitesimal. Thus basing fault on the creation of, or failure to minimize, a substantial risk rather neatly it seems to me sorts out all the causes in the chain leading to plaintiff’s injury into those to which liability may attach and those to which it cannot while simultaneously disincentivizing and incentivizing conduct that respectively creates or fails to abate a substantial risk.

All in all it’s a good opinion (hooray for the Palsgraf mention!) but it wasn’t the “risk as the unifying theory of negligence jurisprudence” opinion for which I’ve been waiting.