Ummmm.......
Some good advice here but also some erroneous advice.
If your friend has her own auto policy then her liability coverage will apply. Liability follows the policyholder, not the vehicle, in
most states.
You may also be shit out of luck with your insurance company if the policy your parents has is limited only to drivers listed on the policy. This is not an unusual restriction when purchasing a policy for a car where a child (not necessarily a minor) is listed as the primary driver.
What you do is call your broker and ask about the coverage limitations and find out if your friend has a policy in her own name. You can tell them anything you like about the accident. You won't be dinged so long as you do not file a claim. Ask your broker about liability law (whether it follows driver or vehicle) and tell them the truth about what happened. Your broker will tell you what to do. Be aware they may go after your friend if she has a policy or they may sue her outright.
You have got to address this with your broker. The reason for this is the subrogation situation mentioned above. The guy your friend hit with your car may file a claim under his own policy and then his insurer will come after your insurer for the damages. You do not want your parents to suddenly find themselves in this situation.
Now, I'm assuming this all happened here in good old New York. If that's the case, your friend is the one who is going to pay because she took your car without your permission. The guy who was hit by her will have to go after her insurance company providing she has one. If she doesn't, they'll have to get the money from her somehow (think
court). You will have to swear an affidavit describing the events to the best of your knowledge. She may come back and claim she had your permission. Your insurance company will back you if you claim she didn't have your permission.
Quick thing to note here. If the car doesn't belong to you but to your parents, then she definitely didn't have permission because they are the people from whom she would legally have to seek permission.
Once again, this is why it's important to contact your broker. New York is a no fault state so there are limitations on who can sue whom for what. Please, please, please, call your broker and tell them what happened. Talk to your parents as well. THEN, and only then, talk to your friend because the fact is, without permission, she's the one on the hook because she used the car without permission of the owner.
My family has a New York state insurance brokerage and we talk about this stuff all the time. Exciting dinner conversation it isn't, but all this has been drilled into my head since I turned 16 and started driving on my own. Don't for a second assume any liability for this either verbally or in a written statement. The other guy was parked and not in his vehicle in a place where one is expected to park a vehicle. As far as his insurance company (and the law) are concerned, he has no liability what-so-ever because nothing he did contributed or could be construed to contribute to the collision. Had he been in a moving vehicle or even behind the wheel while stopped, then different law applies.
Yes, this could get ugly really quickly if your friend isn't honest.
If you're curious as to my credibility,
check out this very situation on insure.com.