Eviction defenses, security deposits, and habitability.
Massachusetts courts apply both the U.S. Constitution and the Massachusetts Constitution to landlord–tenant disputes claims. When state protections are broader than federal ones, Massachusetts judges follow the state rule. When they are equal or narrower, federal precedent controls under the Supremacy Clause.
Federal cases governing landlord–tenant disputes include controlling U.S. Supreme Court decisions and binding precedent from the federal circuit covering Massachusetts. Civil remedies most often proceed under 42 U.S.C. § 1983, with defenses including qualified immunity.
Legal information, not legal advice. For advice on your situation, consult a licensed attorney in Massachusetts.