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Wild Misconceptions About Forensic Science
The Forensic Scientist and the Crime Scene Investigator Are the Same Person
Most crime lab series and films will often show a forensic scientist or technician dashing off to the scene of a crime where he collects the evidence and proceeds to investigate the case. In truth the forensic technician and the crime scene investigator (CSI) are two very separate professionals.
Forensic scientists are usually trained in analyzing forensic evidence and their main area of operations is usually a laboratory while a crime scene investigator is trained in the observation of a crime scene, as well as in the collection of evidence from a crime scene.
Another core difference is the qualifications required of both professions. To enter into the job arena of a forensic scientist one must have a Bachelor of Science degree in chemistry, biology and/or forensic science. In the case of a Crime Scene Investigator individuals do not need to be the holder of a Bachelor’s degree to become an investigator.
Everyone is in the DNA Database
Ever notice how a forensic technician in a crime lab series seems to feed data into a computer and bingo the name of the perpetrator is revealed, who by the way has never even been a criminal before? There is some truth and lies in this depiction.
First off it’s true that various countries have their own DNA databases. The Combined DNA Index System (CODIS) is an electronic database which contains the DNA profiles of perpetrators and is administered by the Federal Bureau of Investigation (FBI). The aim of the database is to help law enforcement be able to compare forensic evidence found at a crime scene to records found in the database.
There is a huge misconception that everyone is in the DNA database. The CODIS currently holds about 6.7 million DNA profiles of convicted individuals, which is insignificant considering that the U.S. has about 300 million citizens. However the recent DNA expansion program could ensure this turns into reality as more and more individuals who are arrested or detained are being added onto the database.
DNA Databases Have Personal Information
One of the biggest misconceptions that Hollywood has perpetrated is that DNA databases often contain personal information of individuals. Am sure you have seen how some forensic technician will feed data into a computer and before you know we have a match. Then up pops your driver’s license, Instagram images, and Facebook and Twitter pages.
Well this is a very big lie! For instance, the CODIS contain no names, driver’s license, social security number, criminal history or any other personal information. The DNA profiles are usually given an assigned serial number identifier, an Agency identifier and the DNA laboratory personnel associated with the DNA profile.
So when a DNA sample is retrieved from a crime scene the sample is simply analyzed and fed into the CODIS software. Once a match is found the forensic technician forwards the information to the indicated law enforcement agency or assigned investigators where they proceed with the case as they see fit. Critics have raised concerns over the databases claiming that they invade privacy and could be used to track individuals or their relatives.
Handling of DNA Evidence
Another misconception of forensic science and labs is that during lab testing procedures on TV the technicians are usually seen munching away at some snack, talking over the evidence, touching themselves and then going ahead to handle the evidence.
Just by talking, coughing or even sneezing over the evidence a technician could easily contaminate it and render the evidence useless. Forensic technicians are trained to handle evidence with utmost care and have to avoid touching areas where any DNA may exist or their own body parts such as the nose, mouth or face. In fact even listening to music can be a distraction that could cause a forensic technician to lose focus and make a mistake while conducting tests.
When it comes to handling of forensic evidence, especially trace evidence, the guidelines for handling evidence is strict and with good reason. For forensic evidence to be used in the persecution of a suspect it must be taken through the right documentation, analyzing and preservation methods.
Perhaps one of the biggest misconceptions about forensic science is that technicians can get results in a matter of minutes once the DNA evidence is collected. Well you should know that this is the real world and it’s much harder than what is portrayed on TV.
If any usable evidence is to be collected then the evidence must be taken through the right procedure which includes cleaning, documentation and analysis of evidence a process which could take up a timeline of up to 54 hours for a single case.
The issue is further complicated by several issues that delay the process. Some of these delays are as a result of using the CODIS software which only allows a laboratories’ server to conduct searches only once a week and it usually takes time before the technician receives a response. This combined with the shortage of forensic scientists and existing FBI backlogs truly makes for a long wait of several weeks to months.
Patience is truly a virtue in these parts of the woods.
All DNA Samples Are Valid
Another big lie that Hollywood has managed to spread through young minds and enthusiasts, is that all DNA samples collected is simply passed on to the forensic laboratories where they are tested without hesitation and are considered valid.
Well it’s time for a reality check. While it is true that DNA samples can be collected from most body tissues and fluids such as saliva, semen, cheek swabs and blood not all samples are routinely accepted by the forensic testing labs.
If the sample is to be accepted without hesitation some forensic testing laboratories require that the DNA sample be accompanied with proper identifying information, history in support of the analysis request and details showing the full chain of custody of the evidence. This ensures that the evidence is not compromised especially if it’s to be used in law proceedings. If however these needs are not met then the sample is automatically rejected making it invalid.
There Are No Errors in Forensic Science
In Hollywood once the incriminating evidence, usually a fingerprint, a lock of hair or a bullet fragment, is located its usually game over for the bad guy and before you know it we have a match and the bad guy gets locked up. Sounds simple, right?
Sorry don’t fall for the over glamorized hype surrounding forensic science to catch bad guys. Reality is much more complicated as forensic science has been known to have errors which if not carefully checked could lead to the conviction of an innocent individuals as is the case with Mr. Odom who was wrongly convicted of rape and has already served 20 years in prison.
There have been calls by the National Academy of Sciences to address issues of accuracy, reliability and validity in the field of forensic science. Forensic techniques which are currently being used have been shown to be subject to human bias and lack standards.
Ever notice how in your favorite crime lab series the perpetrators slightest touch something which the investigator later finds and from that they can swiftly get the DNA of the perpetrator from. Well the depiction is a half-truth, what they normally depict is something referred to as Touch DNA.
Touch DNA refers to the DNA that is usually left behind when a person touches or comes into contact with something. By touching something it is believed humans shed off skin cells which are then analyzed to reveal the DNA of an individual. This means that fingerprints left behind on a particular item or surface may have DNA.
It should, however, be noted that not all fingerprints have DNA. The presence of DNA is influenced by a variety of factors such as the number of sloughed cells, the amount of perspiration produced, how long an individual has been in contact with a particular item or surface and the individual themselves.
DNA Can Be Retrieved from Cremated Ashes
Somehow the lengths that Hollywood will go to produce an entertaining and thrilling episode is beyond comprehension. Forensic scientists in a particular scenario will need to test the cremated remains either to identify a particular person or link them to a particular crime.
Even though there is a growing need for the identification of cremated remains the ability to retrieve DNA from a cremated corpse still remains elusive. This is because the heat and energy that a corpse is subjected to during cremation breaks the bonds between the DNA polynucleotides which essentially destroy the DNA itself.
In some cases, however, it is possible to retrieve some DNA. This is especially true if the corpse is subjected to temperatures lower than 1500 degrees Celsius which could mean that some teeth and bones may still remain intact and some form of DNA analysis can be conducted to retrieve some DNA. It should be noted that the process is unreliable and may or may not yield expected results.
Don’t you just love how Hollywood has the ability to turn any drab job into a glamorous adventure-filled profession? Forensic scientist or technicians are often depicted chasing bad guys in the latest modified sports cars, muscle cars and even Hammers while wearing expensive suits and the latest accessories.
Forensic scientists just like most of us have the same work environment (LINK 20). They operate on normal business hours with their work normally restricted to the laboratory. From time to time they may have to work overtime on an urgent case. Although not unheard of it’s hard to imagine that a forensic scientist could be able to afford the latest high performance vehicle with a pay of around $52,000 per year.
With such a salary and all the other commitments they may have its ridiculous to think that they would splash it out on top of the range vehicles and flashy clothes, which I might add no one will see since most of the time forensic scientists are required to have their laboratory coats at all times while in the lab.