"I don't know how long the investigation would have taken" if Simmons had not turned himself in, Matt Hoover, Bucks County assistant district attorney, said Wednesday.
Simmons faces one to seven years in prison if found guilty of the third-degree felony charge of leaving the scene of a fatal accident, Hoover said.
He also was charged Tuesday with reckless endangerment, driving with a suspended license, failing to help a victim, and failing to report an accident, according to court records. District Justice John J. Kelly Jr. released Simmons on $500,000 bail.
Rearick was hit just after midnight while walking "in the westbound lanes of travel with his back to oncoming traffic," police said in court documents.
Simmons had picked up a prescription for his pregnant girlfriend and was headed to their home on Atkins Avenue at the time of the accident, his lawyer, Louis Busico, said.
"He's a decent, hardworking, honest person who extends his sympathy to the Rearick family," Busico said of Simmons. "This is an accident that hurt two families."
Simmons and his girlfriend have two children, and he works at Rosenberger's Dairies in Levittown and a liquor store in New Jersey, Busico said. He does not have a criminal record, the lawyer said.
As for taking 17 days to turn himself in, Simmons "consulted with his minister and his father and decided to come forward to save law enforcement any further efforts," Busico said.
Police are still investigating the accident, including whether alcohol affected the driver, Hoover said. Busico said Simmons does not drink alcohol.
Hoover declined to comment on whether drugs or alcohol had caused Rearick to walk on the five-lane road, or where the victim was before the accident.
Rearick grew up in Levittown, where he "loved to fix things like lawn mowers, weed whackers, and snowblowers," neighbor Nick Gushue said.
The family's lawyer, Mark Zlock, said Rearick "was always interested in helping people," including being an organ donor.
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