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If ghosts existed, particularly angry spirits embittered about the unfair ways their lives ended, I imagine they'd be huge fans of forensic science. It's easy to picture ghostly victims of murder and injustice cheering for such scientists in the process of obtaining revelatory findings as if watching a playoff game on which they had bet a large sum.
One such historical mysterious death surrounds 17 skeletons at the bottom of an old well. The remains were discovered in 2004, when an area in Norwich, England was excavated in preparation for building a shopping center.
The skeletons were initially thought to be plague victims, yet carbon dating of the remains placed them between the 12th and 13th centuries, before the time of the plague in England.
Analysis by DNA expert Dr. Ian Barnes revealed a DNA sequence in five of the skeletons that traced them to a single family of Jewish descent. While exact circumstances surrounding the deaths are impossible to learn so long after the fact, experts who worked the case believe the deaths were linked to religious persecution. They are thought to be the result of either mass execution or mass suicide, as the possibilities of natural deaths were scientifically discounted. The remains were eventually laid to rest in a Jewish cemetery.
Read about eight other cases of mysterious deaths of old that have been clarified thanks to modern forensic testing here.