Legal Question in Landlord & Tenant Law in California

Whether you can be forced to buy renters' insurance depends on whether you signed a month to month or a long term lease, and if a long term lease whether it is coming up for renewal or has rolled over to month to month. Any month to month tenancy can be changed on 30 or 60 days notice (depending on how long you've been in the property). Any long term lease can be changed when it expires or when it rolls over into a month to month tenancy. So unless you are under an unexpired long term lease, they can force you to buy the insurance. And while they cannot directly evict you for it, they can terminate the tenancy if it is month to month, or refuse to renew if you are on a long term lease, and once the month to month is terminated on proper notice, or the lease expires, then you are a squatter and they can have you evicted at that point.

I don't believe that a landlord can evict you for not purchasing renters insurance. But if they are making that a requirement, and you refuse, assuming that your lease has expired and you are now month to month, they can give you notice of termination and have you evicted if you don't move. Since you have been there a year, you are entitled to 60 days written notice. If you are under rent control, they may not be able to terminate your lease.

If you like where you live and don't want to move, it may be simpler to just buy the renter's insurance. It does not cost that much for a simple policy. It may cost more to move.