Legal Question in Real Estate Law in California

Re: my roomates moving out, and refuses to pay the rent on her lease

When two people sign a lease as co-tenants, they are usually "jointly and severally" liable for the rent. This means the landlord can expect to get the entire rent from either co-tenant; if co-tenant 'X' leaves, the landlord can collect 100% of the rent from remaining tenant 'Y' (or, if he so chooses, can hunt down 'X' and collect from her). However, the landlord can't double collect.

Between 'X' and 'Y,' the story is different. The two co-tenants would be considered to be in a contract to share the rent. If 'X' decides to move out on her own, she remains liable to 'Y' to reimburse 'Y' for half the rent, if 'Y' has to pay it on 'X's' behalf.

Hope this explains it. There are a few additional wrinkles such as a possible 'duty to mitigate damages' but you are not obliged, in my opinion, to take on an incompatible new roommate just to lessen the impact on your former roommate.

If you get stuck with a substantial amount of excess rent cost, you could perhaps sue the former roommate in small-claims court.