I had to go rekey an apartment unit for a lady whose keys were stolen when I noticed that the front door to her building was missing the deadlatch that came with the lock. The guy who installed it either didn’t have the right backset or took the deadlatch that came with the lock to sell to somebody else. It is really unprofessional to install a lock on an exterior door without a deadlatch because anybody can open the door with a credit card or butter knife. See bypassing of the passage latch below.
