A 16-year-old boy accused of fatally shooting a popular neighborhood advocate during a botched carjacking Thursday in the Spring Garden section of the city was free on probation after being found guilty of robbery this year, according to Juvenile Court records and police.
His 21-year-old brother, allegedly with him when Gerard Grandzol was shot, had also been placed on probation, in May, after selling drugs in Center City, the records show.
As a result, Homicide Capt. John Ryan said Monday, police were still trying to determine how Marvin Roberts and his older brother, Maurice, obtained the 9mm handgun that the younger brother allegedly used to shoot Grandzol, 38. Their criminal records or ages should have prevented either from buying the firearm legally.
“We don’t know where it came from,” Ryan said, adding that police had not recovered the weapon.
Marvin Roberts, of Tioga, was adjudicated delinquent on one count of robbery and inflicting a threat of bodily injury in a case filed Jan. 5, the records said. Counts of simple assault, reckless endangerment, and theft were dismissed.
Additional details — such as how and why a judge decided on probation — were unavailable because Roberts was charged as a minor, and state law permits the release of only certain information about juvenile cases. But Ryan said Roberts had been placed on probation for the crime.
On Saturday, the younger Roberts was arrested and charged as an adult with murder, robbery, carjacking, and related offenses in the shooting death outside Grandzol’s home on the 1500 block of Melon Street.
Police have said he and his brother approached Grandzol, the father of two girls, after Grandzol drove home from playing Frisbee in Lemon Hill with his 2-year-old daughter and dog.
The brothers demanded that Grandzol turn over his wallet and keys, police said, but after Grandzol said he wanted to get his daughter out of the backseat of the vehicle, the younger Roberts shot Grandzol twice in the face at point blank range. The girl was still in the car, police said.
Neighbors and friends described Grandzol as a warm and thoughtful person with a diverse set of interests and a broad group of friends. A GoFundMe page set up after his killing had raised $168,000 as of Monday afternoon.
The Roberts brothers were captured on surveillance video at the scene and on SEPTA cameras that allegedly recorded them fleeing north on the Broad Street Line.
Ryan said police arrested the younger brother Saturday near Broad and Venango Streets, and the older brother in Budd Lake, Morris County, N.J. Maurice Roberts was awaiting an extradition hearing Monday, Ryan said, and was expected to be formally charged following his extradition.
Maurice Roberts, of Frankford, had a criminal record before the killing, having received a 12-month probationary sentence in May after pleading guilty in two drug-related cases, court records show. The records say he was caught selling marijuana outside a Wawa store on the 1300 block of Walnut Street, and later on the 1500 block of Market Street.
An earlier drug-related case, in 2015, was dismissed for lack of evidence, court records show.