There are many things that law enforcement officials must do when they arrive at a crime scene.
However, their primary goal is to collect evidence that can help solve the crime. Evidence can be in the form of physical objects and substances or verbal accounts from eyewitnesses.
Typically, some of the first things that law enforcement persons will do upon arriving at a crime scene are to clear the scene of bystanders and tape the scene off.
The question is, what goes on behind that tape.
Securing the Scene
When emergency personnel arrives at a crime scene, they will tape the scene off, and if they notice any injured parties or fires, they will administer first-aid and call for emergency medical teams or other appropriate emergency personnel. Photographers will take photos of victims and injuries, as well. There is usually no “set” steps for this process, as there are typically many things going on all at the same time.
Administering First Aid
While one officer may have the job of clearing the area of bystanders, another officer may have the job of administering first-aid to injured persons and calling for help. In addition, there may be one or two officers who will question witnesses and victims, while a team of specialists partake in such activities as photographing, sketching and collecting evidence. All of these professionals are essential in handling and processing a crime properly.
It is essential for law enforcement teams to secure the crime scene as soon as possible. This will help prevent any disturbances to the scene and any possible evidence. They will typically use tape to block a scene off, but they can also use such things as blockades, florescent flags or vehicles. They should also have a few sentries around the boundaries of the crime scene to make sure that no bystanders try to get into the scene. The only persons they should allow into the scene should be emergency personnel.
Conducting the Walk-Through
After officers have administered first-aide to those people whom need it, called for necessary help and secured the area, they will then need to conduct a walk-through. During the walk-through, they will take note of such things as blood spatters, footprints, weapons, shell casings, strands of hair and any other physical evidence. They must take extra care not to disturb anything until they have photographed and documented everything.
Handling Distraught Persons and Children
There are often several distraught persons at crime scenes; and, in some cases, there may be one or more children. If this is the case, officers need to do their best to calm these people down, and make the children feel safe and secure. Spending a few moments talking to upset people can help calm them. Many police and fire departments also keep a supply of teddy bears or other stuffed animals to offer children during these times of crisis. This can help significantly in making them feel better.
The Importance of Documentation and Photographing
When law enforcement officers process a crime, they need to document everything that they do. They can accomplish this in many different ways; however, they typically use such methods as photographs, notes, digital videos and sketches. They should document everything they see in and around the crime scene, as well as, any evidence they may collect.
They will often use a digital recorder to document what they find, and they will transcribe the notes at a later date. No matter how they choose to document what they find, they must always include such things as a complete description of the crime scene, an accurate list of all evidence found, complete descriptions of each piece of evidence, who found the evidence, when they found the evidence, when they transported the evidence to the crime lab, and a photograph of each piece of evidence.
It is essential that they take photographs of the crime scene and evidence immediately, before anyone has had the chance to touch or move anything. This includes not only the scene and evidence, but it also includes victims and suspects, as well. If the crime occurred outdoors, they should take several pictures of the surrounding area, in addition to the actual scene of the crime. They must also take close-up photos of such things as wounds, bruises, stains and any other evidence that may be difficult to see from a distance.
In some cases, they may need to wait until the victim arrives at the hospital before they can photograph injuries. This occurs when the victim’s injuries need immediate treatment. It is also essential for them to document the size of various things including injuries, stains and scratches. While they typically use a ruler for this, they can also use such things as keys, cigarettes or pencils as size-comparison tools. Sketches can be quite helpful in showing the position of evidence in relation to victims or other evidence.
Collecting the Evidence
After officers have completed the above preliminaries, they will then begin collecting both physical evidence and statements from witnesses, victims and suspects. Typically, only specialists, such as forensics teams, detectives, crime scene investigators or criminal investigators will partake in collecting and processing physical evidence. Not only will they gather such evidence as weapons, but they will also process evidence such as blood spatters, strands of hair, fingerprints and footprints.
While investigators can easily bag some evidence, such as knives or guns, into plastic bags for processing, some evidence is extremely fragile and requires specialized handling. Evidence, such as bodily fluids, can deteriorate if not handled and stored properly. Investigators make use of such things as electrostatic dust-print lifting mechanisms, iodine and superglue fuming to collect such things as fingerprints, footprints and blood splatters. Thus, it is essential that they transport these forms of evidence as quickly as possible to processing laboratories.
Investigators not only need to photograph all evidence and document it, but they also need to handle it properly to avoid disturbing any possible fingerprints on it. They typically accomplish this by wearing gloves before handling any objects in or around the crime scene. They must also package each piece of evidence separately to avoid cross-contamination, and they must properly tag each item before transporting it to the lab.
In addition to collecting physical evidence, officers need to obtain statements from every person at the scene of the crime. This includes not only victims and suspects, but it includes innocent bystanders, as well. This is essential to solving the case and piecing together the steps that may have led to the crime. Even people, whom had nothing to do with the crime, may have something to offer. Thus, it is essential for officers to speak with everyone.
What Does a Crime Lab Do?
After investigators have gathered evidence from a crime scene, they will send it to a lab for proper analysis. Crime lab experts will examine all of the evidence with the goal of solving the crime. They will try to pinpoint the relationship of various pieces of evidence in relation to the crime and the suspect. In many cases, some evidence can offer them clues to help piece together the events of the crime.
Some of the tasks that crime lab technicians conduct include fingerprint analysis, bloodstain pattern evaluation, toxicology testing, DNA testing (of such things as hair, blood or semen), analyzing photos and sketches, analyzing writings and shooting reconstruction. They will also perform ballistic analysis on any firearms to determine if the weapon may have been used during the crime.
Another essential task of crime lab technicians is to restore the serial number on firearms, if it appears that someone has tried to remove the number. Once they can restore the number, they can then trace the weapon to the place that sold it; thus, finding out who purchased it. They will also dust the firearms and other evidence for fingerprints that may point to a suspect.
After technicians have analyzed all evidence from a crime scene, they must store it properly in case it will be required for court proceedings. They typically store evidence in a secure vault within the laboratory that is only assessable to persons working on the case. In the case that evidence is no longer needed, technicians must dispose of it in a safe and proper manner. They dispose of some evidence, such as bodily liquids, in bio-hazard containers.
While some popular TV shows have made crime scene investigations look easy, and made it appear as if investigators can solve cases quickly, handling crimes and solving them can take much longer than people may think. In fact, it is a sad reality that many crimes never get solved. However, when crime scene specialists handle evidence properly and investigate crime scenes thoroughly, they can effectively “paint a vivid picture” of the crime and may be able to solve them.