Such “911 Landlord Laws” are also known as “nuisance” or “crime-free housing” ordinances. The ordinances vary from city to city, but certain elements are common: to keep their rental licenses, landlords are encouraged or required to perform criminal background checks on rental applicants; they are encouraged or required to use a “crime-free lease,” by which any crime on the premises breaks the contract — even if the tenant was a victim and did nothing more than call the police; furthermore, the police can demand eviction of a “nuisance” tenant, and landlords who do not comply can be repeatedly fined or worse. In some cities, landlords can also be forced to pay the cost of police visits.