Legal Question in Landlord & Tenant Law in California

Even if you got a restraining order, it might be of no value because it would probably just limit how close he got to your unit and not keep him off the entire property, especially if he has other friends there, he is able to visit them without coming close to you, etc. So your landlord probably can not evict you for that reason. Assuming you do not live in a rent control city, if you are on a month to month lease, all the landlord has to do is give you a thirty day notice [60 days if you have lived there for a year or more] and he does not have to have any reason for doing so.

Try to get your brother to agree not to visit on the premises, or try to get his friends to agree not to see him there. Tell the landlord that he should tell the other tenants that he does not want him on the premises and for what reason [he better be sure it is true to avoid a defamation suit by your brother]. Point out to the landlord that you are doing as muich as you can to help the landlord, but you are limited by your brother's legal rights.