The Forensic Black List: Infamous Forensic Science Screw-Ups

Every day forensic scientists around the world do their best to further the cause of justice; processing evidence, narrowing the suspect list, and identifying victims. With all the the technology available to us it’s easy to forget that despite our best efforts forensic science is actually part science, part art, and the results of lab tests are often open to interpretation or human error. From bite marks to DNA phenotyping things can sometimes go wrong – terribly, horribly wrong. Here are the most infamous forensic science screw-ups, and what happened as a result.

Annie Dookhan

Annie Dookhan is a former lab chemist for the Massachusetts state drug lab. She worked there for nearly ten years and she was famous for churning out lab results quickly – too quickly as it turned out.

Dookhan eventually admitted to investigators that she falsified many of her results, faked her master’s degree, “dry-labbed” (a.k.a. eyeballed without testing) most of her samples, added cocaine to samples that were actually drug-free, and doctored her reports so that everything looked legit. Needless to say she traded her lab coat for an orange jump suit (she got 3-5 years with 2 years of probation) and her actions led to the dismissal of 21,587 Massachusetts drug cases.

Splitting Hairs at the FBI

In 2015 the Justice Department and the Federal Bureau of Investigation finally owned up to a problem that had been brewing for decades – acknowledging that 26 of the 28 examiners within the FBI lab’s microscopic hair comparison unit gave biased testimony that heavily favored the prosecution 95% of the time while testifying about the hair samples they had analyzed.

While it’s important to note that hair samples and bite marks have long been the black sheep of forensics (they are notoriously unreliable) the biased testimony may still have impacted up to 2,500 cases which are currently under review, including 32 death penalty cases. Even more disturbing is the fact that these same FBI examiners taught their techniques to between 500 and 1000 examiners working at smaller state and local crime labs. A few states have made the effort to begin reviewing affected cases but not all of them, and there is no legal requirement to notify defendants whose cases may have been impacted.

The “Gold Standard” Gets A Black Eye

There have been numerous crime labs which have made mistakes while evaluating DNA – normally considered the “Gold Standard” in forensic evidence. In 2013 the New York City Medical Examiner’s office had to conduct a review of over 800 rape cases after it was discovered that one of their technicians had mishandled evidence and overlooked DNA.

That same year independent consultants hired to review the work of the St. Paul Police crime lab found that the lab had incorrectly classified almost a third of their fingerprint samples as unusable and violated federal safety and health requirements for the testing of DNA, a move which caused thousands of convictions to come into question. Finally, in 2012, Washington D.C.’s prosecutor’s stopped sending DNA samples to the city’s newly created $220 million Department of Forensic Sciences due to technician errors in DNA analysis. 

Sadly these are not stand-alone examples, they are the tip of the iceberg – and part of the problem that led former President Obama’s Council of Advisors on Science and Technology (PCAST) to issue a report in 2016 which detailed the many ways the forensic industry needs to be standardized and adjusted to ensure justice is served. With plenty of new technology on the horizon like familial DNA testing, chemical profiling, 3D printing, DNA phenotyping and even glow-in-the-dark fingerprints it’s safe to say that forensics techniques must be subjected to close scrutiny or we will continue to suffer consequences ranging from invasion of privacy to wrongful convictions.