Every moment of every day involves active crimes and ongoing searches for criminals. Law enforcement and judicial units heavily rely on forensic sciences to solve crimes and analyze crime scenes. Forensic science teams meticulously search for clues that can lead to the identification of thieves or murderers, the weapons used, and any trails left by the victims. Their ultimate goal is to connect potential suspects to the crime scene, using photos and various signs and trails collected during their investigation to determine firstly a suspect and then whether they are guilty or innocent. The process involves examining the crime scene, bodies, fingerprints, online and digital data, blood tests, and more.
The crucial first steps to these are crime scene investigations, which represent one of the foundational and vital steps in forensic analysis. The initial law enforcement teams to reach the crime scene are responsible with keeping any kind of curious crowds, journalists and even unnecessary officers away and attentively examining the scene, but it’s always advised that they never touch anything they find until the forensic investigation reaches the place. First responders have a unique opportunity to observe the crime scene untouched, as any delay can lead to changes caused by both internal and external factors.
To keep the crime scene as close to the first way they found it, the crime scene investigation crews have to move as fast as they can. They aim to understand the movements of potential offenders before and after the crime, the points of entry and exit, and carefully choose where to search for clues. They also have to look out for both the places they can and can’t find clues in so they can use the places that are less likely to safely enter and exit the scene during their examinations. Aside from that, they have to keep the scene protected too, they have to keep any kind of possible intruder away and also be sensitive about not eating, drinking or smoking in the perimeters and about not using any bathrooms or phones either. In some cases they would have to make changes as minor as opening a door, since even the most minute details require documentation to avoid compromising the investigation and have the power to make a difference in whether or not a suspect gets imprisoned.
Another crucial thing that can’t be overlooked is witnesses, since no matter how careful the investigators are, none of them can know as much about the scene as an eye witness as they often hold key information about the scene. The police forces have to be quick and careful to not let any witnesses leave the scene or get harmed before obtaining their statements. Every evidence and clue found alongside with the witnesses’ statements gets filed in the office databases to be used in analyses and legal proceedings.
In a crime scene, there are various signs that tell the story of the crime that took place; could be a blood smear, a bullet hole, a bunch of scratches on the windowsills and so on. While they help with the investigations, none of these bits have much of a value by themselves and wouldn’t give us all the information we need unless put together in a meaningful way that tells us more than we could imagine as one big picture. Sometimes, these kinds of evidence shows us if there was a break-in from seeing if there was any force applied to doors or windows that left marks, or blood streaks that fall on a carpet or splatter against a wall could tell us the force, direction and distance of the blow that hit the victim and if the blood pooled against a surface, it would indicate that the victim had stayed in that place for a while before it was moved. Analyzing these blood samples require extra attention and is not an easy job, so the scientists use precise and delicate equipment to extract as much valuable information from it as they can.
Guns and firearms provide us two distinct clues; one being the bullet hole or wound which leaves an unmistakable mark and shows where the gun was fired from and could even show the very gun that was used, and the bullet casing which usually falls just under the fired gun and thus shows almost exactly where the shooter stood. Guns also leave a trail of invisible gunpowder on the hands and wrists of the shooter that lasts around 6-to-8 hours which is a crucial but time-sensitive evidence for the investigators to find.
Finding a corpse gives the most information about a crime and specifically murder. If someone is reported to be lost by friends or family, depending on the situation, the police forces may not start to look for them immediately. If someone is not a minor and has left or runaway from their house before or show the likeliness or tendencies to do so, the police is less likely to file it as case worth investigating and most probably will not spend time or resources to look for them. If it’s someone below the age of 18 or if their disappearance is not expected in any way by anyone, they’ll be searched for but most likely declared dead if there’s nothing found about their whereabouts after 72 hours. If it’s a kidnapping case, it’s assumed that they will most likely be dead by 24 hours and with less than %1 of survival case otherwise. After a person is lost for 7 years and more, they will legally be declared dead. But before 7 years, if there’s evidence pointing to a murder of the individual, the police may gather enough evidence to make a judgement, imprison the assumed murderer and close the case despite not finding the body.
If a body is found, however, the entire case will go in a completely different way and the assumed suspect may even be proved innocent after the pathologists do their examinations. If a body is found after around 24-36 hours after the death, it is possible to determine almost the exact time of death. The body heat will decrease 0,8 degrees every hour until it reaches the room temperature around it, so if we think about a human body with 36.5 degrees of body heat and the general room temperature 24 degrees, it would take approximately 15 hours for the body to cool down to the equilibrium temperature and if the body is find anytime before those 15 hours they could determine the correct time of death. Alongside the temperatures, there’s rigor mortis, which is the hardening of the body after death. Rigor mortis generally starts in the face area, and in a 6-12 hour time period, spreads to the whole body with the effects of external factors. It’s spread could also be a determining factor in finding the time of death. Color is also another indicator; after the initial event blood starts pooling under the body, giving it an either pink or purple hue depending on the time passed, and if there’s blood pooling in any other part of the body, then they can reach the conclusion that it has been moved at one point or another.
So overall, before the investigators jump to conclusions and then to courts, there’s a plethora of evidence to gather and diagrams to make; they have to find multiple factors varying from every kind of indicator they find on the bodies, the clues and evidence found at the crime scene that leads them to the body to begin with, every mark and scratch on walls and floorboards and every trace of a footstep on carpets, blood splatters and pools, tire marks outside and around or any type of unusual disturbance they can find. It takes all of these and even more of investigating and finding -and protecting- witnesses to be able to find, judge and imprison a criminal.