There are a lot of misconceptions about the effectiveness and reliability of forensic testing. It is not nearly as reliable or foolproof as shows like “CSI” would have you believe. Although many law enforcement professionals understand the limitations of evidence, juries typically do not. Far too many criminal defendants have been convicted based on evidence that was either overstated or simply faulty.
A good criminal defense lawyer would tell you that it is critical to always examine the evidence to see if it can be challenged – even in cases involving lab-conducted drug tests, which are generally among the most reliable evidentiary tests. These tests are still subject to errors, and in some cases, misconduct on the part of lab technicians.
Perhaps the best-known example of lab-technician misconduct came to light about a decade ago and involved a single person working out of a Boston crime lab. During her years in the lab, chemist Annie Dookhan earned a reputation for being fast and efficient. But everything changed when prosecutors discovered that she had been falsifying test results, reporting positive results for tests that were never conducted and lying under oath, among other crimes. In 2013, she pled guilty to a host of offenses and received a prison sentence of three to five years followed by probation.
Her sentence was short in comparison to the damage she did to the criminal justice system and defendants. Tens of thousands of criminal cases were eventually dismissed because it was unclear whether the evidence she provided could be trusted. While certain offenders may have benefitted from having their cases thrown out, others likely faced wrongful conviction based on faulty evidence or received sentences that were disproportionate to what they otherwise might have faced.
The mess is still being cleaned up. In November 2020, a district attorney in Massachusetts sought to vacate an additional 108 cases tainted by Dookhan’s misconduct. Several months earlier, the same DA sought to vacate 64 guilty pleas from drug defendants. Even though they pled guilty, these 64 defendants did so before lab testing of drug evidence had been completed. Once all vacated cases are completed, the DA has said she is committed to helping defendants amend their criminal records.
It is rare for misconduct in the criminal justice system to be so widespread, but misconduct and mistakes do occur in individual cases. Blindly trusting the accuracy of the system is a mistake that criminal defendants cannot afford to make.