Yes, normally if you have comprehensive on your vehicle then this type of physical damage coverage will cover a broken back window on a car that was vandalized.

Comprehensive coverage covers your vehicle, and sometimes other vehicles you may be driving for losses resulting from incidents other than collision (OTC). For example, comprehensive insurance covers damage to your car if it is stolen; or damaged by flood, fire, or animals. It also pays for glass breakage and acts of vandalism against your vehicle. This coverage pays to fix your vehicle less the deductible you choose.

So if the glass broke due to a rock coming through it or an act of vandalism such as a person taking a baseball bat to the back window, it normally would be covered by your comprehensive coverage if you made a claim and paid the deductible that is associated with this portion of your policy.

You can contact your agent or insurance company's claim department to discuss making a claim if your rear window has been damaged due to vandalism.