DNA testing helped investigators bust a 19-year-old Pennsylvania man for a sexual assault that took place in 2017.
Mason Hall was wearing a “dark-colored hooded sweatshirt” on the hot summer day and would have been difficult to identify without the DNA that was recovered in Norristown Farm Park, according to authorities.
The arrest of Hall was announced Monday, three days after he was taken into custody.
“Since we had our attacker’s DNA, we always knew who he was, but it took 27 months of high-tech scientific efforts and thousands of hours of old-fashioned police work to track down this violent criminal and make this arrest,” said Montgomery County District Attorney Kevin Steele. “Rapes and sexual assaults where a gunman attacks an unknown victim are, thankfully, rare in Montgomery County, and we used every avenue available to solve this violent crime.”
Cops say the sexual assault took place just before 11 a.m. on Aug. 1, 2017. It is alleged that Hall, armed with a semi-automatic weapon, forced the 19-year-old woman into a secluded pasture and sexually assaulted her. The woman was attacked from behind, limiting the amount of “descriptive information” that cops had to go on, the DA’s office said.
However, a “composite illustration” of what the perpetrator could look like, based on his DNA profile, was produced, according to prosecutors.
Hall was arrested at his home in Norristown after DNA tests tied him to the brutal crime. Cops had initially narrowed the search to two suspects who lived in the area, but one of them was ruled out based on the description from the victim.
“This arrest represents thousands of hours of focused police work by the two detectives overseeing this case as well as our support staff. These detectives never gave up,” said Steele.
He added that the FBI and the Philadelphia Police Office of Forensic Science provided critical help.
Hall was hit with multiple charges, including sexual assault and involuntary deviate sexual intercourse. He was unable to post bail and was being held at the Montgomery County Correctional Facility.
A hearing is scheduled for Friday.
