Whenever Willard Scott highlights seniors celebrating special birthdays on the Today show, I am struck by how kind the old folks always appear in photographs. At a certain age, their images take on a certain innocence usually reserved for babies.

It has become a running gag with my colleagues at work. As photos of serene seniors flash across the screen, I'll sometimes call out criminal charges for which the old folks might have been arrested in their youth.

Twisted, I know. But my point is that there are bad folks among us. And they, too, get old. Just because someone lives to a ripe old age doesn't mean he or she has a noble life. Take William Barnes.

Barnes has led a life of crime and is now 75. He's spent two-thirds of his years in the slammer, most notably for having shot and incapacitated a Philadelphia police officer in 1966. The young cop was Walter Barclay, who caught Barnes breaking into a beauty salon in East Oak Lane. Barnes shot Barclay, leaving him a paraplegic. For that crime, Barnes was sentenced to 10 to 20 years, and he served the full 20.

"He was bad at his craft and spent more time in prison than on the street," author Allen Hornblum told me. Hornblum met Barnes while researching his book Confessions of a Second Story Man, about local gangsters, and he is no apologist for Barnes. He's familiar with Barnes' history of violence and many jailbreak attempts. And he knows well how Barnes ruined Barclay's life. But Hornblum contends Barnes told him of an epiphany he'd had in the early 1990s after a life of lawlessness that earned him the nickname "Cowboy."

"He was embarrassed for what he'd done . . . including for the fact that his mother was so ashamed she would not walk outside in daylight. And he decided he did not want to die in prison," Hornblum told me.

So Barnes started to play by the system's rules and was finally released from jail in 2005. He worked as a janitor and stockman at a ShopRite in Roxborough and lived in a halfway house on North Broad Street. Then, in August 2007, Barclay died, and then-Philadelphia District Attorney Lynne M. Abraham decided to charge Barnes with Barclay's murder. At the time of his arrest, Barnes possessed a cellphone and car keys, violations of his parole. As noted by U.S. District Judge Timothy R. Rice, who reviewed the case, "He promptly waived a hearing and admitted to the technical violations of his parole, and the Pennsylvania Board of Probation and Parole determined he should serve six months in custody for the violations."

Make that six months and four years.

Barnes is still in jail. His attorney reported Thursday that parole had finally been granted, but no release date had been set. In recently ruling on a petition for writ of habeas corpus, Rice detailed the revolving door of reasons that have been asserted for Barnes' continued incarceration.

Barnes' attorney claimed his client was being held because of the parole board's "arbitrary, pretextual, and vindictive denial" of his parole applications, which "violates his substantive due-process rights." Rice agreed. The board countered, "It has long been established that an inmate whose parole has been revoked has no constitutionally protected right to be paroled again.

"Although Barnes clearly persuaded the magistrate judge that he deserved to be paroled, that is not the standard for federal habeas review of a parole refusal," the board's objection read, listing various reasons for refusal, including that Barnes posed "an unacceptable risk to the community."

In a footnote to his opinion, Rice wrote that, with regard to the murder charge, "Barnes rejected an offer to plead guilty to third-degree murder, despite the fact that he would have been entitled to credit for the time he had served in connection with the shooting. That time nearly equaled the maximum sentence that could have been imposed for third-degree murder."

Had he pleaded guilty to the murder of a police officer, Barnes would be out, but because of the cellphone and car keys, he remains behind bars. Of course, it's not really about the cellphone and car keys.

Rice also recounted how, after Barnes' acquittal on the murder charge, the assistant district attorney on the case wrote to the parole board and said Barnes "remains the same vile criminal that he was" decades ago, "despite his outward appearance of a frail, elderly person." Rice concluded the prosecutor falsely asserted Barnes "has yet to serve the full sentence" he received in the 1960s for shooting Barclay and demanded that Barnes "should spend the rest of his life in prison."

In case there was any doubt as to whether this case was about contraband that Barnes had when rearrested, the prosecutor attached an autopsy photograph of Barclay's legs. And so Barnes sits at Graterford while the legal wrangling continues.

I'd be content to let him sit there until death had a jury sentenced him to life in prison for shooting and incapacitating Barnes. That would seem like a just punishment. And Barnes' niece Diane agrees with me.

"My brother is a police officer, and I believe in today's society you should never, ever walk out of prison if you shoot a cop," she told me last week. "But back in 1966, that was not the case. He spent 20 years in prison, and it should be over.

"If they wanted to keep him in prison, they should have done so back in 1966," Diane Barnes said. "That is not the case. We had a trial, and they found him not guilty. And the commonwealth is saying we don't care what the jury found."

She's right.

This isn't a case about a burglar who shot a cop and was sentenced to life in prison. It's now a matter of whether we will honor the rule of law.

Contact Michael Smerconish via www.smerconish.com.

Read his columns at www.philly.com/smerconish.