Criminal Investigation Techniques

One of the most important purposes of physical evidence is to establish the identity of a suspect or victim. Some of the most valuable clues at a crime scene are fingerprints. "Processing a crime scene" is a long, tedious process that involves focused documentation of the conditions at the scene and the collection of any physical evidence that could possibly shed light on what happened and point to who did it.

Every crime scene has evidence and there is an extended process that must be followed in order to properly mark and preserve any evidence. Once an initial search of a crime scene has been done and all photographs or sketches have been completed it is then that investigators should begin collecting evidence. Each police agency has specific policies and procedures that should be followed during the process of collecting evidence.

We live in a society where large parts of crimes such as; rape, assault, and burglary involve gun violence. One of the newest controversy surrounding the topic of gun control is the procedure known as “ballistic fingerprinting.” The impact of ballistic advancement has played a critical role in unraveling new levels of solving crimes in the criminal justice system. Ballistic fingerprinting specifies to a set strategy that depends exclusively on the imprints that a firearm leaves on a bullet to match it to the gun used to commit the crime. Ballistic fingerprinting requires gun manufacturers to test-fire the firearms they produce and store pictures of the ballistic markings left on the cartridge cases in a database so that law enforcements can

Crime scenes are known to have many clues left behind. The obvious would be a the body or bodies, clothing, and sometimes even the murder weapon. While these are great way to solve a case there's another kind of evidence; trace evidence. Trace evidence are small pieces of evidence that are laying around a crime scene. There are many types of trace evidence some of them include metal filings, plastic fragments, gunshot residue, glass fragments, feathers, food stains, building materials, lubricants, fingernail scrapings, pollens and spores, cosmetics, chemicals, paper fibers and sawdust, human and animal hairs, plant and vegetable fibers, blood and other body fluids, asphalt or tar, vegetable fats and oils, dusts and other airborne

From a trial strategy point of view, you always start with the piece(s) of evidence you believe are most damaging to the client's case and work backwards looking for an exploitable flaw in the search and seizure procedure that would make that or those item(s) inadmissible. The further back in the series of events you can argue a fatal flaw, the more likely that the evidence and any additional materials which flowed from that particular item of evidence will be excluded. This is the practical analysis of all the times we see or hear of law enforcement arguing that there was some technical item which drew their attention and suspicion and justifies their hunch that criminal activity is afoot.

There are different ways law enforcement can prove evidence and the guilty with impression evidence. Latent (invisible) or patent (visible) prints that are used in criminal investigations are typically collected from crime scene specialists to reveal or extract fingerprints from any surface or objects with the use of chemical or physical methods. Fingerprints can be shown when they are taken from a crime scene where the crime was committed. Fingerprints and bite-mark evidence have similar traits to shoe prints and tire tracks that can be used in criminal investigations. There are a percentage of palm prints that must be left at the scene to make a comparison for valid evidence.

That is a good question, one worth answering. Forensics is a scientific tool that has come to its own starting about the 80’s. Fingerprinting was one of the first techniques used to help in identifying the criminals that committed the heinous acts. Fingerprinting uses a brush and powder to enhance the ridge details on the fingertips adhering to the oils left behind. Another awesome way they have been able to pull prints off soft surfaces like bed sheets is by using superglue and heat. Fascinating isn’t it? Since then Forensics has become even more evolved. Fingerprints now go into a database known as AFIS or Automated Fingerprint Identification System, which has the prints of everyone

Firearms evidence is a key to capturing a shooter. Firearms evidence can be found at different types of crime scenes; from homicide to rape. Forensic technicians can determine the distance of a shot based on power residue, they can compare cartridge cases and bullets to particular guns possibly used at the crime scene and link them to owners, forensic technicians can also determine the sequence of shots fired and trajectories. Gunshot residue found at a crime scene can be matched with that found on suspect’s hands. When a firearm is located at a crime scene, a forensic technician must first of all diagram and photograph it before collecting it. It is important to treat every firearm found as if it were loaded. Every situation must be carefully

It is a guarantee that every American has watched or read something about a criminal investigation. With so many popular shows, movies, and books all with the same basic plot, it is almost impossible not to. Criminal Investigation stories are everywhere, including in a recent Disney movie where a bunny must solve a seemly unsolvable case and catch the bad guy. The stories always follow a similar pattern. The hero detectives invoke on a criminal investigation to solve a case, they collect evidence and begin to solve the case piece by piece, and at the end, the case is solved and the criminal is apprehended. All criminal investigation stories follow this similar pattern. Not all things are shared but there is one thing that always is: the criminal.

According to the National Institute of Justice, the majority of homicide in America is committed with firearms. In 2011, data collected by the FBI show that firearms were used in 68 percent of murders, 41 percent of robbery offenses and 21 percent of aggravated assaults nationwide. For the crimes involving firearms, the most important trace is usually the gunshot residue. When someone uses a firearm to commit a crime, the discharge from the gun will be deposited on the crime scene, the victim, and also the perpetrator. Studying gunshot residue is critical in a crime investigation, since it is useful in reconstructing the event and identifying a suspect, and there have been a lot of studies done in this area.

I am Detective Sergeant Marcus C. Albright assigned to the Criminal Investigative Unit with the Maury County Sheriff’s Department and was so on the 29th day of December, 2017. I was contacted earlier this week by Sara E. Myers who is with the U. S. Attorney’s Office from the Middle District of Tennessee about attending a meeting with Mary Catherine Elizabeth Thomas at her attorney’s office. Tentatively I was informed the meeting with her attorney Jason Whatley was to explore possible information the U. S. Attorney’s Office had gotten regarding a relative of Tad Cummins communicating with Mary Catherine sometime over the last couple of weeks.

In forensic science, corpses from various homicides are different. There are both complete and incomplete corpses, depending on the causes of death or the forms of homicide. For example, some corpses are cut into pieces, some are camouflaged by dumping into the river, some are buried, some are burned to destroy the evidence, and others. If the corpses are incomplete, it can lead to the difficulty of personally identifying because some tissues and bones are destroyed.

Fingerprints are detailed, difficult to alter, and permanent over the life of a person, which makes them suitable as a long-term identifier of an individual. They also can be used to identify people who are deceased in the aftermath of a crime. The recovery of fingerprints from a scene is an important part of forensics in identifying a possible suspect. Blood is often found at various types of crime scenes, such as homicide, assault, rape, robbery and burglary. Blood type can be an identifying factor to assist investigators to narrow the search for a suspect. With DNA typing technologies, an individual bloodstain can now be used to identify an individual of a crime or a suspect. Blood spatter can also be used to identify which hand a person used during a stabbing, the direction of a shot and even the distance of the shot from the victim.

The precise distance from which a handgun or rifle has been fired must be determined by means of a careful comparison of the powder residue pattern located on the victim’s clothing or skin against test pattern’s made when the suspect weapon is fired at varying distances from a target. The conclusion that can be deduced if a fine droplets of a victim’s blood are found inside the muzzle of a firearm at an outdoor crime scene where the victim suffered several gunshot wound; the gun is a physical evidence in which a fingerprint will be lifted from the gun. And the gun was used in committing the crime of shooting therefore, it was the gun that shot the victim.

must take the measurements of the area roped off, and if there is evidence on the ground or anywhere, that specialist must make a two-point measurement, which means, take two unmovable objects of that area like a door or an outlet and measure how far they are to the evidence. The sketcher must also draw everything else in the crime scene in order for the computer in the forensics lab to get the most accurate measurement. If there is a crime in a small town that doesn’t have a crime scene unit then a detective will have to carry out all these tasks while also interviewing witnesses and tracking down suspects to solve the crime.