Does a tenant have the right to change the front-door lock(s) of her apartment?
Answer
The short answer is no, unless you inform your landlord first and he/she does not repair it. It is yery important to read your lease first. Always inform the landlord first that the lock is broken and the immediacy of the necessity of the repair. Your landlord has a duty to give you a warranty of habitability, which means that all "rental housing accommodations be maintained in a safe and sanitary condition for the tenants. " Section 235 of the Real Property Law. If your safety is immediately endangered, such as in domestic abuse cases, you may repair the lock first and then notify the landlord.
"Multiple Dwelling Law 51-c specifically permits tenant to change a door lock or add one, but he must supply a duplicate key to the landlord upon request." (Wolfe v Frankel, [App Term Oct. 3, 1979]
See also the case of Sherin v. Bvk Hsre Reit where the tenant sues the landlord for damages after landlord did not put a lock on the room that was rented. The court discusses the warranty of habitability in detail.
(Sherin v BVK HSRE Reit I LLC, 81 Misc 3d 1228[A], 2024 NY Slip Op 50025[U] [City Ct 2024])
The following code provisions are applicable in New York City:
New York City Housing Maintenance Code §27-2008 ("Owner's right of access"): "No tenant shall refuse to permit the owner, or his or her agent or employee, to enter such tenant's dwelling unit or other space under his or her control to make repairs or improvements required by this code or other law or to inspect such apartment or other space to determine compliance with this code or any other provision of law, if the right of entry is exercised at a reasonable time and in a reasonable manner. The [Department of Housing Preservation and Development] may by regulation restrict the time and manner of such inspections." (For those regulations, see Rules of the City of New York §25-101.)
New York City Housing Maintenance Code §27-2009 ("Tenant violations as grounds for eviction"): "Any conviction of a tenant for violation of this code which: ... (3) Consists of an unreasonable refusal to afford access to the dwelling unit to the owner or his or her agent or employee for the purpose of making repairs or improvements required by this code, shall constitute grounds for summary proceedings by the owner to recover possession of such dwelling unit from the tenant."