Properly investigating a crime scene is essential for law enforcement to determine what has occurred and gather the data necessary to identify and locate the perpetrator of the crime. While exact methods of conducting a crime investigation will vary depending on national and local laws that apply to the work of crime investigators, there are several elements that are bound to be involved in any type of crime investigation.
One of the first events to take place with a crime scene is to secure the general area. There are a number of important reasons for this. First, chances are there is evidence at the scene that will aid in the crime investigation. Fingerprints, DNA, elements of the general state of the area, and other factors may be key in identifying suspects once the investigation is in full swing. Often, investigators allow no one outside law enforcement into the scene until a thorough inspection is made.
Along with securing the crime scene, police also must identify the victim of the crime. In situations where the crime is an assault or burglary, this step is fairly straightforward. Should the crime in question be murder or if the victim is unconscious, the identification process may take more time to complete. However, the crime scene itself may yield information that makes the identification process relatively easy.
Witnesses to the crime are usually interviewed as quickly as possible by qualified investigators. It is not unusual for the investigator to collect contact information from each witness, making it possible to contact them at a later date if necessary. Eyewitness reports often yield clues that would otherwise make it more difficult to evaluate the evidence and begin the process of compiling a list of possible suspects.
Once a preliminary interview with the witnesses is done, it is normally time to document the site. This is often done with the use of video and the creation of still photographs. In most cases, the stills are taken with a high quality digital camera, making it easier to use computer technology to isolate and enlarge various sections of the shots if necessary.
The collection of evidence from the scene of the crime normally commences as soon as the documentation phase is complete. Samples may be taken of body fluids or any other liquids at the scene. Often, a criminal investigation will also include collecting clothing, hair samples, or other objects or materials that may aid in the process of DNA profiling or obtaining clear fingerprints from the general area.
Once the initial processing of the crime scene is completed, the office files a crime report, including all relevant information regarding the nature of the crime. From that point, the collected evidence is evaluated, a list of suspects is established, and the process of finding the criminal gets underway in earnest.
The crime investigation is perhaps the single most important process in the field of criminology. Highly methodical, the success of any investigation relies on the ability of the investigators to expertly assess all the evidence, zero in on the perpetrator, and bring the culprit to justice. In some cases, the crime investigation may be a quick and clean process. At other times, a complex investigation may take years or even decades before any conclusive results emerge.
