If an employees car is vandalized in the employee parking lot is the employer responsible for damages?

No, the employer is not responsible.

Even if it is a private parking lot owned by the owner, it's no different than your car being vandalized and broken into at Wal Mart. Where you park is your choice at the end of the day, and the owner of the lot is not responsible for those that come onto the lot and commit crimes.

There is no argument for you being forced to park there because you work there. It just doesn't work that way.