A crime scene is any location that may be associated with a committed crime. Crime scenes contain physical evidence that is pertinent to a criminal investigation. This evidence is collected by crime scene investigators (CSI) and law enforcement. The location of a crime scene can be the place where the crime took place or can be any area that contains evidence from the crime itself. Scenes are not only limited to a location, but can be any person, place, or object associated with the criminal behaviours that occurred.

After a crime scene has been discovered, measures must be taken to secure and protect the scene from contamination. To maintain the integrity of the scene, law enforcement must take action to block off the surrounding area as well as keep track of who comes in and goes out. By taking these precautions, officers can ensure that evidence that is collected can be used in court. Evidence that has become contaminated, tampered with, or mistreated can pollute the scene and cause a case to be thrown out of court.

Everything that occurs during the analysis of a crime scene must be documented. It is the job of the initial responding officer to make sure that the scene has an extremely coherent and summarized documentation. The documentation should include the officer's observations and actions while at the scene. The initial responder is in charge of documenting the appearance and condition of the scene upon arrival. The initial responder will also gather statements and comments from witnesses, victims, and possible suspects. Several other documents are also generated so that a crime scene's integrity is kept intact. These documents include a list of who has been in contact with evidence (chain of custody), as well as a log of what evidence has been collected.