Forensics, which is basically the practice of applying science to crime, dictates that certain procedures be followed at the scene of a crime. The first officer to arrive at a crime scene must take certain steps to preserve life and evidence. Only after these duties are performed can analysis of the scene begin. These steps include:

  1. Assuring his or her personal safety and that of any fellow officers, victims, suspects, and witnesses.

  2. Offering first aid to any injured persons and calling for medical help.

  3. Calling for backup and any ancillary personnel, such as detectives, crime-scene investigators, coroner’s office personnel, and firefighters, that are deemed necessary.

  4. Cordoning off the scene to protect the integrity of any evidence.

  5. Detaining and separating any suspects or witnesses whenever possible.

  6. Establishing a security log for any and all persons who enter or leave the crime scene.