Forensic science is formally defined as any of the sciences that are used to answer legal questions. The actual term forensics is derived from the Latin, forensic, which translates to “before the forum”. Normally many types of science and scientific procedures are used to prove points in relation to a civil action or crime. Some of the earliest uses of forensics date back to 1248, though more modern uses originated in the 16th century. This is a very broad scientific field that contains many subdivisions.
Crime Scene Investigation
Most individuals are familiar with forensics in relation to crime scene investigation. The main purpose of the crime scene investigator is to establish what occurred, also known as crime scene reconstruction. This process requires careful documentation of the crime scene, the ability to recognize evidence and collect evidence. Tasks include taking pictures of the crime scene, making note of the weather and lighting, and determining if any objects are out of place.
One important part of evidence gathering is fingerprinting. Each person has small ridges on the hand and these ridges form different patterns. Because this ridge is raised slightly from the rest of the skin it produces a print on surfaces. Finger prints are present even if they cannot be seen due to the oil found naturally on the skin. The application of special powder will bring out the pattern of the fingerprints. Each person’s fingerprints are unique and therefore it is possible to identify an individual by their fingerprints. The state and legal system contains records of fingerprints from anyone that has committed a crime as well as many non-criminal individuals. In the United States this system is known as the Integrated Automated fingerprint Identification System and is managed by the FBI. Unidentified prints can be matched to those already in the system.
This branch of forensics combines techniques from medicine, biology and chemistry. Specifically it concerns the symptoms, treatments and detection of poisoning. Frequently in forensics it is up to the toxicologist to determine if any chemicals were the cause of death. This individual is not necessarily concerned with the legal outcome but instead with obtaining and then interpreting the test results. Toxicologists typically will be responsible for identifying any powders, medicines, and any other solutions found around the crime scene or in the victim. Toxicologists will normally have to analyze blood, hair, oral fluids, urine and other fluids using gas chromatography, spectroscopy, X-ray diffraction, immunoassays and other tests.
Besides fingerprinting, technology has advanced enough that DNA matching or DNA profiling can be used to identify individuals. The majority of DNA is the same in each person, but 1% is different. This small difference is enough to properly identify each person. There are several different techniques that are used in DNA matching including STR analysis, RFLP analysis, AmpFLP, PCR analysis, chromosome analysis and mitochondrial analysis. There are several DNA databases found around the world. Just as with fingerprinting the DNA of unidentified DNA is compared to those in the databases. DNA evidence is very important to criminal cases.
This branch of forensics uses computational methods to study and solve problems within the forensics field. Computer simulation, computer modeling and computer recognition can be used to help support forensic analysis. These methods can produce likelihood ratios for the possibility of certain theorized results, can help to increase effectiveness and efficiency of casework. There is also a specific branch of computational forensics known as computer forensics that focuses on studying digital evidence.
This science is applied to forensics to determine the cause of death and normally incorporates an autopsy of the body. Besides performing autopsies the pathologist may also be required to confirm the identity of the corpse. Forensic pathologists are medical doctors that specialize in anatomical pathology. This individual can determine any diseases, injuries or other processes that have led to death; this is known as the mechanism of death. This mechanism of death is then used to determine the manner of death which can be accidental, homicide, suicide, natural or undetermined.
Trace Evidence Analysis
This type of evidence identification refers to those that are very small, as materials can be transferred to other substances by friction or heat. In forensics trace can be used to solve crimes by determining location and people involved in the crime, normally to reconstruct the crime. Some examples of trace evidence that may be present at crime scenes include volatile hydrocarbons from fires, paint chops, hairs, mineral fibers, explosive residue, soil, gunshot residue, cosmetics and other items. Analysis typically begins with a visual examination of the evidence but then will change to microscopic analysis that uses comparison microscopes, scanning electron microscopes and stereomicroscopes. Other useful tools include X-ray and chemical tests.
Famous Court Cases
The first case to use fingerprint evidence was in 1892. By comparison of a fingerprint left at the scene of the crime the inspector convicted Francesca Rojas of beating her children to death. Another famous fingerprint case was the murder of Thomas Farrow in 1905. He was a shop manager located near London and a thumbprint was found on the cash box of the store. Eventually police found a match to the bloody fingerprint and two men were hung for murder. This was the first instance where fingerprinting was used in a murder case.
Another famous case that relied on forensic handwriting analysis was the Lindbergh Kidnapping in 1932. The 20 month son of the famous aviator, Charles Lindbergh, was kidnapped and a ransom was paid. The child was never returned and by tracing the money police were led to Bruno Hauptmann. Key testimony matched Hauptmann’s handwriting to that on the ransom note. Additionally scientists found a match between the wood found in Hauptmann’s attic to the wood used for the ladder to kidnap the child.
Forensics was key to the conviction of Machine Gun Kelly a notorious criminal from the 1920s and 1930s. Kelly kidnapped a rich oilman, Charles Urschel and received $200,000 in ransom. Despite the fact that Urschel was blindfolded when he was kidnapped he remembered the weather, timing of a thunder storm, animals he heard nearby, estimated when planes flew overhead and left his fingerprints all over the room. His memories allowed the FBI to determine the location of his kidnapping and his fingerprints were found linking him to the location, which caused Kelly to be sentenced to life in prison. Other cases that relied heavily of forensics include the Green River Killer in Washington, the BTK killer in Kansas, the Night Stalker and Ted Bundy
One of the first famous individuals to use forensic evidence was the fictitious detective Sherlock Holmes. This character was actually based off of a famous forensic scientist, Joseph Bell, one of Conan Doyle’s teachers in medical school. Other famous characters that use forensics include Miss Marple and Hercule Poirot from the popular books by Agatha Christie. Forensics has even been used in comic strips as Dick Tracy used many forensic methods and Barry Allen (the Flash) was a forensic scientist in the police department.
Many television shows have used forensic science with the most well-known being CSI. Many other shows that incorporate forensics in solving crimes include, Midsomer Murders, Criminal Minds, Bones, NCIS, Monk, Dexter and Waking the Dead. Several movies that are based around forensics include the Bone Collector, Pathology, Murder by Numbers, Code 33 and Angels Don’t Sleep Here. The basic plot of these movies is that cops or doctors used different types of forensics to solve crimes or catch a murdered.