Crime scene investigation is a complex and intricate process. Since not all crime scenes are the same, the process of investigating them is not fixed. Investigators use many individual tactics and procedures to perform a successful crime scene investigation. There is, in fact, a checklist in the brain of every crime scene investigator. Though there is no uniform crime scene investigation procedure, there are usually some universal steps followed by every investigator to conduct a successful crime scene investigation. From collecting shreds of evidence and photographing the crime location to taking fingerprints, there are some crucial steps in every investigation.
1. Securing the crime scene
On reaching the scene, the crime scene investigator (CSI) first establishes the boundaries of the crime scene. This is done using a crime scene tape and putting sentry at all possible entrances. The area or structure must be secured by controlling ingress and egress so that no further disruption can be caused to any potential physical evidence.
Once the investigator locates the main area of the disturbance, a radius of the focal point with all the immediate physical evidence is to be created. Usually, investigators prefer to make a large radius so that spectators do not miss or disturb potential evidence. A yellow crime scene tape or rope or cones is mostly used as a barrier, creating a common entryway. Every person entering and leaving the area is to be documented. In addition to this, CSI must identify and remove any hazardous materials or weapons from the location.
2. Take the first-round survey
Evidence plays a central role in prosecuting a case. To collect evidence, CSI conducts the first round of crime scene surveys. He walks around the structure’s exterior to check for obvious evidence, such as open windows, damaged doors, or ladders. While conducting the scene walkthrough, the lead investigator will identify and take photos of important evidence. Then, he searches for evidence inside the building. At this time, they will take photographs of the scene, note weather conditions, check if the lights were on or off, note down the exact position of items such as furniture, the presence of any smells, etc.
3. Assess the location and note down details
The first look at the crime scene gives an idea of what type of evidence must be present. The CSI thinks about what must have happened when it happened and what evidence to be looked for. This includes the possibility of removing blood and other evidence by the first responders or family members, signs of struggle, or visible footprints in the blood. Based on all the physical evidence available, the CSI prepares a narrative of the scene to give the impression of the stage.
4. Conduct a detailed search
Now, it’s time to locate even the smallest particle of evidence and collect fingerprints. This includes using a vacuum to manage potential microparticle evidence, such as hair and fibers. Also, all the possible physical evidence is captured photographically with medium-range and close-up shots. In addition to this, CSI also prepares a rough sketch of the scene. Sometimes, the investigator may use a videographer to present a better idea of the scene to a jury for more complicated cases. It is essential to keep all the evidence in proper containers. The evidence with bloodstains must never be packed in plastic bags to prevent them from decomposition. Also, all the evidence must be properly labeled.
5. Perform a Final Survey
Proper crime scene investigation is fundamental in deciding the case in the future. Thus, a skilled investigator ensures that no single piece of evidence goes ignored. In the final survey, each team member participates so that no potential evidence is left by chance and no error in the documentation. Once the team is satisfied, the crime scene is released.