Of 28 examiners with the FBI Laboratory’s microscopic hair comparison unit, 26 overstated forensic matches in ways that favored prosecutors
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The cases include those of 32 defendants sentenced to death. Of those, 14 have been executed
Hair isn't DNA. The tests done on it are comparative afaik.
In fact, in the linked article it says that DNA exonerated people tried based on hair comparison – 25% of those exonerated to boot. Sounds like DNA is great.
What you seem to have a problem with, which is valid, is procedures, how evidence is introduced, and how the authority/validity of that evidence is communicated to the court, correct me if I'm wrong.
Hair testing is not considered proper DNA testing, as far as I understand. In fact the article you linked to mentions that wrongfully convicted persons were often exonerated via subsequent DNA tests.
Of 28 examiners with the FBI Laboratory’s microscopic hair comparison unit, 26 overstated forensic matches in ways that favored prosecutors ... The cases include those of 32 defendants sentenced to death. Of those, 14 have been executed