A criminal investigation is a police process that includes gathering evidence and analyzing it to identify potential suspects. This is an ongoing and critical part of any criminal case, involving everything from homicide to burglary.
At the heart of any criminal investigation is a careful, structured approach to questioning witnesses and analyzing physical and digital evidence. A police investigation should be impartial, and investigators should follow all reasonable lines of inquiry until they have gathered sufficient evidence to determine the truth or to dismiss a suspected offender.
In a criminal investigation, law enforcement professionals follow strict protocols to ensure the integrity of the crime scene and preserve all available evidence. For example, they mark and document each item at the scene, noting its location, size, condition, and other important details. This documentation helps prosecutors reconstruct the crime scene in court and provide context to jury members.
Officers also learn to notice details that might help them solve a crime. They will note the position of weapons, blood stains, and fingerprints, as well as the presence or absence of a victim. They also document witness statements and their own observations. This is a critically important part of the process because contamination of trace evidence can destroy an investigation. For instance, the JonBenet Ramsey murder remains unsolved in part because family and friends inadvertently contaminated physical evidence in their search for the body.
The timeline to identify a hit-and-run driver varies widely, depending on the case’s priority and the quality of the evidence. For example, cases involving serious injuries see 3-5 times more investigative hours allocated compared to property damage-only incidents. In addition, clear surveillance footage from traffic cameras and doorbell or business camera systems accelerates identification, sometimes reducing investigation time from weeks to hours.