If you are a tenant in the apartment you have a right to possession of the premises until the end of your lease or rental term which can only be be reduced or terminated by a court order on an action brought by the person with whom you have directly contracted to pay rent - the landlord or the tenant to whom you are a sub-tenant. Nobody has the right to the self-remedy of a lock out while you are in rightful possession and in some jurisdictions to lock you out is borderline criminal. Contact your local police, show them proof the apartment is your legal address, and have an officer escort you to the apartment at a time you know your roommate is home. You can also complain to your landlord, but the police escort is going to make a greater impression on the roommate.
Answered on Oct 14th, 2011 at 1:32 PM