My Car Got Towed, Can i Just leave it there?

Hey my car got towed from in front of my home it was on the street and it had expired tags, anyway i live in california the car is from Arizona and i never registered it here becuz i didnt work so i was gonna dump it. The day they picked it up i had just parked it to rearrange my garage anywho the police dep. wants me to register my car and buy insurance for a car that doesnt work so its gonna cost me more than 500 just do so the car is not even worth that much..Well My question is..its at the towing yard and what can i do if i dont want the car do i just leave it there and forget about it? or do i have to let them know im not going for it? Let me know guys if i do get the car it goin straight to the junk yard so what can i do?