I am a victim of domestic violence and the abuser has a gun. Is that legal?
It depends. If you have a protective order (DVRO) against the abuser, California law says that s/he cannot have or buy a gun. See I have a DVRO against the abuser. Can s/he keep a gun or buy a new gun? for more information.
Also, federal laws, which apply to all states, restrict a person's right to have a gun under certain circumstances such as when the abuser has been convicted of certain domestic violence-related crimes or if you have an order of protection against the abuser that meets certain requirements. Go to Federal Gun Laws to get more information.