Forensics is trusted by the authorities on convicting criminals for more than a century. Fingerprints, blood splatters, DNA, bit marks, shoe impressions, etc. are solid physical evidences that can associate a person with the crime, crime scene, or even put him on death row. Yet, forensic sciences are under strict scrutiny in the recent years. A lot of misjudgments are convicted because of wrong forensics.
The father back to the crime scene with Detective Stabler, the DA and the independent investigator/ professor for reenactment. (Source: Screen shot from Torch, Law & Order Season 11)
If you are a crime drama fan like me, you may have watched every episode of Law & Order, CSI, or NCIS, to name a few. Yet, when talking about forensic scrutiny, Torch, an episode from Law & Order Season 11 particularly rings a bell.
Let me walk you through the storyline:
The episode begins with an apartment caught a fire in the middle of the night, and two young girls died in a burning house. They were left in the house by their father, not because he did not try to save them. He did, yet the fire was too vigorous. He failed and burnt his hand. The (SENIOR, as he claimed himself) fire marshal concluded the fire was set by the father with incorrect assumptions he made. These assumptions were disarmed by an independent investigator/ professor, together with a real reenactment of the scenario—burning the DA’s house!
This episode alerts the public the danger of forensic sciences, or the danger of junk sciences. In fact, it does not only happen in drama but happens frequently in the reality.
In the documentary Forensics in Trial (watch here), it criticizes and investigates the uniqueness of fingerprints, the science-ness of bite marks. Jessica Gabel, a law scholar, commented that “forensic bit mark evidence is more art than science;” a lot of interpretation is needed indeed. In this case, should we still trust forensic sciences (are we, the forensics lovers living in our little fantasy)?
Both DNA and autopsy are hard sciences. The former is chemistry, and the latter is biology/ human anatomy. Are these two secure enough to convict crimes? Autopsy, for instance, may not be as accurate as it is. In the recent Michael Brown case, the autopsy is problematic. Shawn Parcells, the man that assisted in Michael Brown’s autopsy has his credentials questioned. He presented himself, according to Mail Online, as a pathologist even though he was not.
DNA, a well-known crime conviction technique, plays a critical role in cases such as the famous OJ Simpson case. Even the DNA evidence ties OJ Simpson to the crime scene, it took the jury only four hours to decide he is not guilty. Why? Because the plaintiff could not prove the evidences are beyond reasonable doubt in order to convict OJ Simpson. Part of the doubts is the legitimacy of evidence. The evidences had lost the chain of custody; police were accused for contaminating the crime scene, and plated evidence to frame Simpson. These all come together to show that even though the person was guilty, once the evidence did not speak the exact same story, no crime will be convicted.
By the same token, in 2012 a forensic chemist named Annie Dookhan had falsified thousands of drug tests. She had also mixed up evidence samples, fabricating results so as to be the most productive chemist in the lab, and lied about credentials.
All these examples just to illustrated one thing: it is not the science is false but the interpretation, and the person who interpreted the evidences are fractured. Quoting attorney McShane from Dookhan case, saying “a forensic scientist in a courtroom is that of a neutral scientists, not as part of the prosecution team…it’s the duty of a toxicologist to focus on the chemistry and the pharmacology not to concentrate on the conviction.”
Like any crime drama, people working in forensics and law enforcement do have a sense of justice, and what does it mean to each of them. One should not forget that being a good scientist, or even just law enforcement agent, professionalism and open-minded thinking are both critical.
The coolness of forensics is the accuracy of conviction. Mistaking one step would make killers walk free, while sending innocents to jails, even on death row.
Spargo, Chris. 2014. “The mystery of Shawn Parcells: How forensics ‘expert’ without a medical degree assisted in Michael Brown’s autopsy amid claims he stole a body and lost a brain.” Mail Online.
Trager, Rebecca. 2014. “Hard Questions After Litany Of Forensic Failures At US Labs.” Chemistry World.