"You blame your dad," said Wallace's sister, Nancy Kolenkiewicz, looking directly at Shaffer. "Well, you're a coward and a crybaby and a criminal."
Shaffer had testified at trial in January that his father, a veteran city firefighter, had a volcanic temper. Shaffer said he accidentally knocked Wallace to the ground trying to prevent his father from beating the inebriated pedestrian further.
Her voice filled with sarcasm, Wallace's widow, Marie Elaine Wallace, told Shaffer "this had nothing to do with your upbringing. This was a choice that you made, a choice to be violent, a choice to be a punk."
Wallace called the Shaffers "the perfect beating team. He was the one who set this in motion and you finished it."
Shaffer and his father were arrested after the fatal attack on Wallace on April 8, 2010 at Knights and Fairdale Roads in the Northeast.
Shaffer's father, a 23-year veteran city firefighter, died at home of a heart attack on Dec. 5, 2011 at age 48.
Shaffer Jr. was charged with third-degree murder, which carries a 20- to 40-year prison term, but the jury found him guilty of involuntary manslaughter, a misdemeanor under Pennsylvania law.
Speaking in a barely audible voice as he stifled tears, Shaffer apologized to Wallace's family and insisted that "I wanted to stop my father from being a bully and help Mr. Wallace."
The incident that ended with Wallace's death began about 7:30 p.m. on April 8, 2010. Witnesses testified that Wallace was crossing the intersection and walked in front of Shaffer Sr.'s gold Dodge Durango, stopped eastbound on Fairdale at the light.
Shaffer began honking his horn and swearing at Wallace to get out of the way; Wallace yelled back that "I have the right of way."
Witnesses said Shaffer Sr. parked the SUV, got out and pursued Wallace on foot north on Knights Road and confronted him at the entrance to a gas station.
Wallace held his hands up and backed away, witnesses testified, repeating that he "had the right of way." Shaffer pushed Wallace in the chest and knocked him back several steps. Wallace approached and threw a punch and the pair started fighting.
Shaffer Jr. got out of the SUV vehicle and ran to the fight calling after his father. Witnesses said the son pushed his father out of the way, grabbed Wallace in a bear hug and flipped him over his shoulder and headfirst into the concrete.
Both men got back into the SUV and drove off. Wallace died of massive brain injuries two weeks later.
Defense attorney James A. Funt urged Ransom to sentence Shaffer within the state sentencing guidelines for involuntary manslaughter: 3 to 12 months with credit for 6 months Shaffer spent in jail in lieu of bail awaiting trial.
Assistant District Attorney Peter Lim argued that Shaffer should get a sentence that reflected his troubled past including a juvenile sexual assault conviction and a history of violating probation by using marijuana.
"The defendant and his father went nuclear over a small infraction," Lim added.
Contact Joseph A. Slobodzian at 215-854-2985, firstname.lastname@example.org, or @joeslobo on Twitter.