There is a misperception that forensic sciense is flawless but miscarriages of justice caused as a result of bad science are not uncommon.
A report from the National Research Council in 2009 highlighted that many forensic techniques had no scientific basis. The National Commission on Forensic Science (NCFS) aimed to explore these issues and recommend changes to bolster the field. It brought together forensic scientists, lawyers, judges, law enforcement, victim advocates and independent scientists. In 2017 however, Jeff Sessions, the new attorney general refused to extend the term of the NCFS and the commission disbanded. During its four years of existence, the NCFS sought to bridge the gap between scientific and legal disciplines, and recommended that forensic techniques be validated independently before being used in investigations. Such an approach is the norm for the development of medical therapies, airplanes and electrical devices. Forensic techniques, however, have not been subject to similar requirements, leading to instances such as that of Keith Allen Harward, who was convicted of murder and rape on the basis of bite-mark evidence, which has long been shown to be flawed. Harward was later released on the basis of DNA evidence.
You can read the full article in Scientific American.