The daylight rape was as shocking as it was brazen. A 19-year-old woman, walking alone in the pastoral Norristown Farm Park, had a gun pressed to her head in the waning days of summer 2017 and was pulled into a secluded wooded area.
And for two years, Montgomery County District Attorney Kevin R. Steele had obsessed over the case. He and his staff, Steele said Monday, began to “think outside the box.” They posted a $10,000 reward. They consulted with prosecutors in California who caught the “Golden State Killer.” And they submitted their only clue, the attacker’s DNA, to strenuous testing at a lab.
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The key break in the case came from a genetic profile created for investigators by Parabon NanoLabs, a scientific laboratory in Virginia, using DNA left behind after the assault.
With that profile, investigators began to essentially work backward, looking for the then-unidentified suspect’s family members in publicly available databases. They found some local matches, and after interviewing them, developed two suspects, according to Steele.
One of them was Hall, who detectives later discovered had been arrested in Norristown a month after the rape was reported, according to the affidavit of probable cause for his arrest. In that case, the teen was arrested for allegedly vandalizing a car with a hammer.
The instrument, stained with Hall’s blood after he cut his hand on the auto glass, was still in evidence, the affidavit said. With help from Philadelphia police, county detectives in September compared the blood with the DNA from the park.
It was a match. Hall was taken into custody at his home late last week after trying to flee from police, Steele said.
DNA links Montgomery County teen to violent 2017 rape in Norristown Farm Park