Who is in fault if a uninsured car slides down a slope and hits a car parked illegally?

I'm not an attorney either, but that seems like a situation in which fault would be shared. An uninsured car cannot be on a public roadway - ipso facto, it never should've been there in the first place, and the conclusion can be made that the accident wouldn't have happened if the car wasn't on a public roadway. On the flip side, the person parked illegally shouldn't have been there, either. In such a situation, both parties are likely to be cited, and the person with the uninsured car isn't going to be compensated by the insurance company covering the other car.

Disclaimer: I am not an attorney. But that seems to be a thing at the discretion of the Judge, all conditions must be considered, and 'illegally parked' could mean anything from an expired meter to blocking the road. And in Calif, if you are uninsured, regardless, you are at fault because you should not have been on the road. If you rear-end a car at a red light, and that car, just sitting there waiting at the light, is at fault if uninsured. That's why you should carry both uninsured and under- insured on your policy, even when convicted and ordered to pay, they usually don't.