Am I liable if someone gets drunk at my house and drives home if they are over 18 and they crash

If you plied her with liquor and then let her drive away an aggressive attorney might sue you too. Normally this kind of liability is belongs to a bar who keeps serving an obvious drunk but it might work against you too. Consult a NJ attorney on this site.

You could be. There are not enough facts to really make a good determination. You should contact an attorney right away and tell them the entire story.
Attorney Jason Chan
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Disclaimer: I am licensed to practice law in MA. Any information that is provided is for informational purposes only.

I don't practice in NJ. It depends. Do you mean criminally or civilly liable? It is much more likely that you would be involved in a civil lawsuit -- negligent entrustment. It could also transpire that the person brings you in as a witness to the affirmative defense of involuntary intoxication -- they didn't know you were getting them drunk -- in the criminal case against them.
Edward J. Blum

Thank you for your email.
There are Social Host Liability laws in New Jersey for a situation like this. A critical issue is whether or not this person was served alcohol in your home while he/she was visibly intoxicated and what efforts, if any, were made to restrain the person from dirving if he/she was in fact visibly intoxicated prior to departure.
If this occurred in a home, and assuming you have homeowners insurance, then you would forward any lawsuit filed against you to your insurance carrier to defend you (they should provide you with a lawyer for free as to negligence based counts).
You may wish (and need to) to retain personal legal counsel if you are sued and your insurance company is not covering all of the claims that may be potentialy filed against you.
Good luck.