We've Been Using The Wrong Science In Court For 50 years

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Bloodstain pattern analysis became widely accepted after Herbert Leon MacDonell’s 1971 book, built on experiments in his basement.
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Paramedics accidentally transferred a homeless man’s DNA from their equipment to a murder victim. He was charged and held five months while hospitalized.
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In 268 FBI cases from the 1970s through 1999, DNA review found 96% of hair-analysis conclusions were false.
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In a 2013 NIST study, 69% of laboratories analyzed a four-person DNA mixture incorrectly. Only 21% called it inconclusive.
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In a study creating 89 cadaver-skin bite marks, none matched measurements from wax impressions or the original teeth.
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Nine people were executed and 33 sentenced to death before errors in microscopic hair analysis were discovered.
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Bloodstain pattern analysis entered courtrooms more than fifty years before its first baseline reliability study in 2014.
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There is still no minimum quality or quantity threshold for DNA samples. Each laboratory decides when a sample is too mixed or partial.
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Across 411 models, the model that made a skin bite mark was not even its closest match.
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DNA from four or more people becomes increasingly difficult to compare with a suspect’s clean profile as signal strengths overlap.
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DNA evidence is powerful for identifying individuals, but it cannot be interpreted separately from the surrounding context.
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A large 2021 study found analysts reached different conclusions about a bloodstain’s creation approximately 8% of the time.
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The largest DNA contributor on a shared object is often the person who shed the most cells, not the last person who touched it.
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Forensic examiners need insulation from police and prosecutors to make independent decisions based on relevant scientific evidence.
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Bloodstain analysts use stain dimensions, physics, biology, and trigonometry to infer impact angles and trace spatter to its origin.

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