How do the police investigate crimes?

When the police receive a report of a crime (such as a home burglary in progress), they send investigating officers to the scene as soon as they can. If the officers arrest a suspect, they will transport that person to the police station or the jail for booking. The officer will write an arrest report, detailing when and why the officer went to the scene, along with any observations, and why the officer arrested the suspect. The officer also will fill out a property report, detailing what items (for example, drugs or cash) the police found on the suspect during booking. The officer also will list any items of evidence found at the scene, such as tools the suspect might have used to gain access to the home.
If the crime is complex or serious, the police then assign an investigating officer (usually a detective) to the case. That officer will make a return visit to the crime scene, look for more evidence, and interview any other witnesses. If the police have not arrested anyone, the detective will analyze the evidence and try to narrow down the list of suspects. The detective will question suspects and sometimes will obtain a confession.
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