National Institute of Justice
A Guide for General Crime Scene Investigation
Arriving at the Crime Scene
Part 01.
Initial responding officers who arrive at a crime scene should:
Respond with caution. Officers who arrive at a crime scene must be cautious and methodical. They should strive to preserve the scene with minimal contamination and should not disturb physical evidence.
The responding officer(s) should:
Note or log dispatch information (e.g., address/location, time, date, type of call and parties involved).
Be aware of any persons or vehicles in or leaving the crime scene.
Approach the scene cautiously, scan the entire area, and note any possible secondary crime scenes.
Make initial observations (look, listen, smell) to assess the scene and ensure officer safety before proceeding.
Remain alert and attentive.
Treat the location as a crime scene until it has been assessed and determined to be otherwise.
Follow safety procedures. Officers must identify any dangerous situations or people to keep themselves and other individuals safe.
The responding officer(s) should:
Ensure that there is no immediate threat to other responders— scan the area for sights, sounds and smells that may present danger (e.g., hazardous materials such as gasoline). If the situation involves a clandestine drug laboratory, biological weapons, or radiological [opens in pop-up window] or chemical threats the officer should contact appropriate personnel/agencies before entering the scene.
Approach the scene in a manner that maximizes the safety of victims, witnesses, officers and others in the area.
Survey the scene for dangerous persons and control the situation.
Notify supervisory personnel and call for assistance/backup.
Provide for emergency care. Officers should ensure that medical attention is provided to injured people, and minimize contamination of the scene.
The responding officer(s) should:
Assess the victim(s) for signs of life and medical needs and provide immediate medical attention.
Call for medical personnel.
Guide medical personnel to the victim to minimize contamination or alteration of the crime scene.
Point out potential physical evidence to medical personnel, and instruct them to minimize contact with such evidence (e.g., ensure that medical personnel preserve all clothing and personal effects without cutting through bullet holes, knife tears, etc.).
Document movement of persons or items by medical personnel.
Instruct medical personnel not to clean up the scene and to avoid moving or altering items originating from the scene.
Obtain the name, unit and telephone number of attending medical personnel, and the name and location of the medical facility where the victim is to be taken.
If there is a chance the victim may die, attempt to obtain a dying declaration or a statement about the circumstances surrounding his or her impending death.
Document any statements/comments made by victims, suspects or witnesses at the scene.
If the victim or suspect is transported to a medical facility, send a law enforcement official with the victim or suspect to document any comments made and preserve evidence. (If no officers are available to accompany the victim/suspect, stay at the scene and ask medical personnel to perform this task.)
Secure and control people at the crime scene. Officers should control, identify and remove people from the crime scene.
The responding officer(s) should:
Control all individuals at the scene — prevent individuals from altering or destroying physical evidence by restricting movement, location, and activity while ensuring and maintaining safety at the scene.
Identify all individuals at the scene, such as:
Suspects. Secure and separate.
Witnesses. Secure and separate.
Bystanders. Determine whether they were witnesses, if so treat as above, if not, remove from the scene.
Victims/family/friends. Control while showing compassion.
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