When crime scene investigators gather evidence, they often take it to a lab for processing. They try to connect the hair samples, shoe prints or blood spatters they found at the crime scene to the suspect or potential perpetrator.
Yet, some tests run by scientists may not give reliable results. According to the Innocence Project, more than 354 people were released from prison after further testing of DNA evidence proved their innocence. Misapplied forensic science was involved in 52% of those cases. Erroneous and misinterpreted test results can lead to a wrongful criminal conviction.
Unreliable testing procedures
Studies show that certain testing procedures do not produce reliably accurate results. While someone may have been convicted of a crime based upon evidence processed using these invalidated tests, scientific advancements may show that they were actually innocent of committing a crime.
For example, researchers found that evidence obtained using microscopic hair follicle analysis is often overstated, misleading the judge or jury to believe the single comparison is enough to link someone to the crime. The same situation is true with shoe print and tiremark comparisons.
Inaccurate interpretation of information
Not only have some tests been scientifically discredited, but the information obtained from running evidence tests may also be misread or miscommunicated to others. Even reliable forensic testing procedures may be run incorrectly by lab technicians. Scientists may misinterpret information or place too much importance on it during an expert testimony. This can paint a misleading picture to jurors, who may then convict a suspect based on wrong information.
It is critical that forensic evidence testing is conducted properly, producing accurate and reliable results.