Higher standards of forensic testimony and crime labs

For many years forensic experts have testified in case after case about techniques—like fingerprinting, ballistics and hair comparison—that have never lived up to true scientific standards. And yet the law requires that when expert witnesses testify, what they say has to be based on reliable science. In effect, forensic evidence has had a free pass when it comes to being admitted in court, and IPNO thinks that our courts need to start being more careful.

Courts should question whether every forensic technique offered in a criminal case can really support its overblown claims of accuracy and reliability. Some forensic techniques—like bite mark examination and microscopic hair comparisons—are based on such shoddy premises that they should never see the inside of a courtroom again. Other techniques—like fingerprints or firearms identification—need merely to be seen for what they are: tools that can narrow down the pool of suspects, but not reliable methods for conclusively identifying specific individuals.

No forensic examiner should be able to testify that they’re “90%” sure that certain evidence came from a specific individual—as a hair examiner did in Anthony Johnson’s trial—when there is no scientific or statistical basis for that kind of probability figure.

In its groundbreaking 2009 report, the National Academy of Sciences (NAS) recommended that crime labs should be independent from law enforcement agencies so that their work would be focused on doing good science, not on building evidence to help the police. IPNO strongly supports creating walls of separation between police and crime labs so that the forensic work remains independent. IPNO also supports greater oversight for crime labs, including heightened accreditation standards, better training, and stronger proficiency testing.

To learn more about the NAS report, click here.

Angola Prision