1. Short title This Act may be cited as the Safeguarding Sanctuary Cities Act of 2017 . 2. Findings Congress finds the following: (1) Existing Federal law authorizes any authorized immigration officer to issue an immigration detainer that serves to advise another law enforcement agency that the Federal department seeks custody of an undocumented immigrant presently in the custody of that agency, for the purpose of arresting and removing the undocumented immigrant. (2) Unlike criminal detainers, which are supported by a warrant and require probable cause, there is no requirement for a warrant and no established standard of proof, such as reasonable suspicion or probable cause, for issuing an ICE detainer request. Immigration detainers have erroneously been placed on United States citizens, as well as immigrants who are not deportable. (3) Galarza v. Szalczyk, U.S. Court of Appeals for the Third Circuit ruled in March 2014 that States and counties are not required to keep undocumented immigrants in jail on immigration detainers