And as his body lay there waiting for the long ride to Valley Forge Memorial Gardens, officers began to file by to pay their respects.
First up was the Highway Patrol motorcycle unit, accompanied by the sounds of machinery.
Next came the Philadelphia Police and Fire Pipe and Drum Unit, whose members filled the air with lilting music.
And last came cruisers from other police departments.
No words were spoken.
At the cemetery, the only words came during a eulogy by the Rev. Frank Lettko of Faith Independent Baptist Church in Roxborough, who recounted the officer's hard life, spoke of his faith in God, and concluded that he was now in a better place.
The interment ended with a fly-over by a police helicopter, and a bugler's sounding of taps.
Throughout it all, Barclay's only survivors - sister Rosalyn Harrison and brother William Sr. - sat stoically.
Barclay died Sunday of complications resulting from being shot on Nov. 27, 1966, while trying to stop a burglary in East Oak Lane. One of the bullets left him paralyzed from the waist down. Afterward, he lived alone for most of his life.
His family said he suffered horribly after the shooting.
Three days before he died, he was admitted to St. Mary Medical Center in Middletown Township.
Bucks County Coroner Joseph Campbell said Barclay died of a urinary-tract infection related to the shooting. Campbell ruled the death a homicide.
As a result, the District Attorney's Office reopened the case to weigh whether the shooter, William J. Barnes, now 71, should be charged with murder.
Barnes, a career criminal who was sentenced to 10 to 20 years for attempted murder and other crimes in Barclay's shooting, has spent more than half his life in prison.
Barnes was taken into police custody while working at ShopRite next to Koller Funeral Home on Tuesday and held overnight at Police Headquarters for questioning.
Barnes has two parole violations against him, said Capt. Benjamin Naish, a police spokesman, but he has not been charged with Barclay's murder. "He will lose privileges because of this parole issue," Naish said. "He will not be allowed to work or travel."
Barnes was returned Wednesday to the Joseph E. Coleman Education and Treatment Center in Juniata, where he has lived since being paroled in 2005.
Barnes has spoken to audiences at Eastern State Penitentiary, where he was once a prisoner, and to criminal justice classes at Temple University about his life of crime and incarceration.
"Bill was hit by the perfect storm - Barclay's death and a recent City Paper article about his speaking engagements - at the same time when he was trying to get his life back together," said Allen M. Hornblum, an urban-studies assistant professor at Temple University who has had Barnes speak to his class.
"Though I believe he got off light in the shooting of Officer Barclay, I don't believe new charges should be refiled now that the officer has died. Barnes has done more than a half century in prison. He does not deserve a medal, but he knows he screwed up," Hornblum said.
"Bill is a gifted public speaker with a powerful message," said Sean Kelley, program director at Eastern State Penitentiary Museum. "He bluntly speaks about why he was in prison here and what life was like. It's raw, sometimes painful, and thought provoking."
Kelley said the museum wasn't condoning what Barnes did. "We will respect whatever the courts decide. It is complicated."
Contact staff writer Gayle Ronan Sims at 215-854-4185 or email@example.com.