You did not mention it but it would appear that the person from your party, that took your car without permission, was either in an accident or caused damage to your vehicle. If it is the damage to your car that you are concerned about this would normally be claimed under your physical damage collision coverage. An accident harming other cars would usually be covered by liability.

Since you did not give the driver permission to drive your vehicle though, it is likely that any liability or collision claim could be denied by your insurer. Many insurance companies will not cover a loss such if your vehicle was used without your permission. Permission is generally one of the prerequisites for an insurance company to cover a claim.

To find out exactly how your insurance company will handle this situation you will need to contact your insurance agent. He or she should be able to explain the insurance company's guidelines as well as your policy terms to you.

As the owner of a car, if the person driving it harmed another person's car you may be held responsible depending upon state laws. If you are held liable for the person's actions and your insurance company will not pay out for any claims on your behalf, you may need to seek legal advice on what your options may be. It would help if you were able to find out who drove your car so that if necessary you could take them to court for the damages they caused to you or others.