Someone side swiped my car while it was parked on a public street in California causing about $1500 damage to both left side doors. My insurance company is ruling this incident a collision and subject to my $500 collision deductible. I should note that I have zero deductible on my comprehensive insurance.

It seems to me that this is vandalism since my car was damaged by an unknown person and should be ruled a comprehensive claim. It shouldn't matter weather they caused the damage with a car or a baseball bat. Who's right?

Have you read the definitions set forth in your insurance policy?

Yes I have and here is how my insurance company defines:

Comprehensive
This coverage pays for the loss of or damage to your insured automobile caused by something other than a collision or impact with another vehicle or object. Coverage will be provided for losses resulting from perils such as fire, theft, vandalism, and windstorm.

Collision
This coverage pays for damages to your insured automobile as a result of collision with another automobile or object or an upset.

Uninsured Motorist Collision Deductible Waiver
Pays for Collision deductible if damage to your car is caused by direct physical contact with an UNINSURED motor vehicle and when the uninsured vehicle and the driver or owner can be IDENTIFIED.

So then, one could argue that this type of damage, a dent to a door by an unidentified person in an unknown vehicle could be either collision or vandalism depending on your point of view. My insurance company is clinging to the narrowest possible reading of the terms because it lets them push a $500 deductible off on me.

Your vehicle wasn't vandalized. It was STRUCK ("accident") while it was parked. Every insurance company that I've ever written for, and every insurance policy that I've ever seen listed an accident in which your vehicle is parked as a collision claim.

Looks like I'd have been better off if they had used a baseball bat!

Not sure what to tell you. Your auto policy has been written like this forever.

I will suck up this $500 because I have no choice. But let me just say, in calling this loss a "collision" I think they are conveniently applying the standards of one type of loss, a driving collision in which I can see the car and driver that hit me, to a completely unrelated type of loss, an act of property damage by an unknown person.

I did nothing wrong and yet I am out $500. BTW, the company in question is 21st Century. Don't know how much it costs them to acquire new customers, but after 5 years, they have lost me.

Okay. However, that this the standard for every insurance company that I have heard of. YOU are the one trying to change the definition. The policy was written long before you ever became their customer. The definition was in place and being used ever before you became their customer. It will be the same definition when you go to the new company. You could have read your policy before you had a loss, and you would have realized this.

You keep referring me back to the policy, as if it's some sort of holy document that is beyond reproach and that I, the ignorant policy holder, should just read my policy for it contains irrefutable language. It is my contention that the definition of comprehensive coverage is intentionally vague (perils such as fire, theft, vandalism, and windstorm.) Such as (but not limited to) is how I read this.

I live in Southern California, where there are almost more vehicles then people, and where getting side-swiped by some deadbeat is a matter of when, not if. With this in mind, I have been paying extra for the last 5 years to have a $0 deductible on my comprehensive. I fully expected to be covered for this type of loss. I am disappointed that it turns out that I am not.

You are right to encourage policy holders to read their policy, but understand, we are not all lawyers or insurance industry professionals. The insurance industry needs to help us use their product in a constructive way, not take advantage of us because they can.