If someone gets drunk at my party, am I liable if they get into an accident?
In some states, under "social host liability" laws, a person who hosts a social event may be on the legal hook for injuries if they provide alcohol to a guest who causes an alcohol-related accident after drinking to the point of intoxication. Be aware that not every state has this kind of law on the books, and the ones that do use different standards for holding a host liable.
Let's look at an example. Let's say Holly invites Damon over to her house for a wine and cheese party. Damon ignores the cheese in favor of glass after glass of his favorite zinfandel, which Holly continues to encourage long after it's clear that Damon has had a few too many. After a few hours, Holly says goodnight to Damon and walks him to his car. At an intersection, Damon blows through a red light and plows his car into Paul's car.
In every state, Paul would be able to bring a personal injury case against Damon over the car accident. And in states that have a "social host liability" law, Paul may also be able to make a civil claim against Holly. But whether Holly is liable depends on the language of the statute. In some states, Holly will only be liable if she somehow broke the law in providing alcohol to Damon (if he's under 21, for example.) Elsewhere, Holly might be liable if she "knew or should have known" that Damon was intoxicated, and/or if she "knew or should have known" that Damon would be driving a vehicle.
It's important to remember that not every state has passed this kind of law; in fact, some states have enacted legislation that specifically shields a social host from civil liability if a guest has too much to drink and ends up causing an accident.
A logical follow-up question is, "Can a guest who gets drunk at my party sue me if they end up getting into an accident?" In other words, can Damon sue Holly if he is injured in the accident? The answer here is almost always no. Even in states that have fairly liberal "social host" laws, liability usually only extends to third parties who are harmed by the intoxicated guest's conduct. A "first party" claim by the intoxicated guest will almost always fail. One notable exception is where a host provides alcohol to a minor. In that situation, a minor who is injured in an alcohol-related accident (even one they themselves caused) may be able to file a lawsuit against the host.
Learn more about Alcohol-Related Accidents and Injuries.