How long is a life sentence? For Pennsylvania’s Supreme Court, a philosophical quandary.

What’s the meaning of “life”?

That’s a question Pennsylvania’s highest court will ponder Wednesday, as it follows other courts around the country in grappling with the question of how many years in prison constitute a life sentence.

And how could such a thing even be calculated? By consulting actuarial tables to assess life expectancy? By referencing the national age of retirement? Or by gauging the chances of coming home with some quality of life remaining?

More specifically, the question before the court is: Is 50 years a life term?

That’s the minimum sentence a Philadelphia court imposed on Michael Felder, whose appeal is now before the Pennsylvania Supreme Court. Felder was 17 years in old in 2009 when he reacted to a dispute during a two-on-two basketball game by retrieving a semiautomatic handgun and using it to strike one of his opponents and fatally shoot the other, teenager Jarrett Green.

The U.S. Supreme Court in 2012 ruled that automatic life-without-parole terms for minors are unconstitutional, effectively overturning the sentences of more than 500 individuals across Pennsylvania and about 300 in Philadelphia, which was home to more juvenile lifers than any other jurisdiction. In response, state lawmakers set new mandatory minimums for juveniles convicted of murder, ranging from 20 years to 35 years depending on the age and classification of the offense. And the state Supreme Court, in response to the hundreds of postconviction petitions flooding in, set new rules: to reimpose life without parole for a juvenile, prosecutors would have to show that the offender was irredeemable, incorrigible, and “irreparably corrupt.”

For Felder to be sentenced to de facto life without such a finding — that would be an illegal sentence, according to his lawyers.

In fact, all sides in the case seem to agree that 50 years is indistinguishable from life without parole. But Felder’s advocates, from the Defender Association of Philadelphia and Juvenile Law Center, argue that it would have to be rolled back to 20 to 25 years to constitute a non-life sentence. The Philadelphia District Attorney’s Office puts forward 40 years as a more appropriate benchmark.

“Life in prison without the possibility of parole gives no chance for fulfillment outside prison walls, no chance for reconciliation with society, no hope,” the U.S. Supreme Court wrote in the landmark case Graham v. Florida.

So, juveniles who are resentenced, Philadelphia public defender Bradley Bridge argues, “need to be released in time to achieve those goals.”

That, he said, is why he rejects the idea of releasing people at the age of retirement, in their 60s.

“When you or I retire at our age of retirement, we have already had a lifetime to get to that point," he said. “We’ve had an opportunity for raising a family, for career, for education — so when we retire at age 65, there is a lot that preceded that 65. These people getting out of prison at 65 have not had these opportunities at all.”

Philadelphia District Attorney Larry Krasner changed course from the previous administration, which opposed Felder’s petition for review by the Supreme Court, in agreeing with Bridge that some prison terms do clearly constitute de facto life sentences, also known as virtual life sentences. (“People die, and they die in less than 100 years,” he said.)

But Krasner, who became a prosecutor in his mid-50s after a lifelong career as a defense attorney, argues that any sentence under 40 years still affords the opportunity to start over and have a meaningful life outside prison. "I’m 58. I don’t think my life was over when I was 42.”

He notes that 25 years — far from being an unusual or extreme sentence — is a commonly negotiated number for first-degree murder in Pennsylvania. Many of the city’s resentenced juvenile lifers agreed to terms between 20 and 30 years in prison.

“Our primary focus is what does any meaningful life outside prison walls mean? As much as any bright line can, we think 40 is a decent, fair bright line,” he said.

Elsewhere in the country, courts and legislators that have addressed the question have come up with a range of numbers (and some have altogether rejected the idea that de facto life sentences for juveniles are illegal). Lawmakers in California, Louisiana, Florida, and elsewhere have drawn the line at 25 years; Nevada, North Dakota, and Washington, D.C., put it at 20 years; and Delaware set the cutoff at 30 years.

Felder’s advocates, including Marsha Levick of Juvenile Law Center, argue that those laws reflect an emerging standard around the country that the court should take into consideration.

Levick herself is reluctant to state a number. “It’s not about quantity of years; it’s about quality of life,” she said.

Yet, it’s hard to imagine settling the question without one. And until that number is identified, it remains unclear how widespread the impact of the court’s decision will be. Just a handful of juvenile lifers have been resentenced to terms longer than 50 years, but many more will be affected if the court finds terms over 25 years to be de facto life sentences. Not only could such a ruling require dozens of individuals to be resentenced for a second or third time, but it would also overturn the current sentencing statute for juveniles convicted of murder, forcing a new debate in the legislature.

Additionally, a number of cases have been placed on hold pending the outcome of Commonwealth v. Felder.

One is that of Michael Foust, who shot and killed two people in a drive-by shooting in Oil City, Pa., in 1993, when he was 17. Foust was resentenced to two terms of 30 years to life, running consecutively — a notable departure from similar cases in Philadelphia where juveniles who killed two or even three people were sentenced to concurrent prison terms, making them eligible for parole in half the time. Levick is arguing that the cumulative 60-to-life sentence is also a de facto life term.

Levick acknowledges there’s a need for accountability, for paying a debt to society. But she argues that, in waiting to release people until they’re elderly, it’s society that ends up paying: “I think there is a very real social and economic cost to releasing this cohort later in life, because they have no skills or resources to fall back on.”