Property rooms or evidence rooms are usually in a police station

Police station

A police station or station house is a building which serves to accommodate police officers and other members of staff. These buildings often contain offices and accommodation for personnel and vehicles, along with locker rooms, temporary holding cells and interview/interrogation rooms.- Facilities...

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They are secure rooms where vital evidence is kept until it can be used in court, or it can be evidence where an offender has not yet been arrested such as a vital piece of evidence recovered from a scene of crime. The rooms are usually very secure as most of the evidence would be key in an investigation to present in court.

All evidence taken in or out has to be tagged, logged and barcoded.