This woman was 18 when she acted as lookout for a fatal robbery. But was she just a kid?

When Avis Lee was just 18, she and two older men went looking for someone to rob outside the Pittsburgh Athletic Association, an upscale social club. Lee was the lookout and says she didn't anticipate anyone would get hurt. But her coconspirator got into a scuffle with the victim, a man named Robert Walker, and ended up fatally shooting him.

Since her conviction for that 1981 crime, Lee has been serving a life sentence — the mandatory term for an adult convicted of first- or second-degree murder.

Tuesday, though, a panel of Superior Court judges held a hearing in Philadelphia to consider whether Lee was in fact an adult.

Lee is arguing that in light of recent neuroscience showing that brain development continues well into a person's 20s, she should be considered a juvenile. That would make her eligible for resentencing under a 2012 U.S. Supreme Court decision, Miller v. Alabama, which referenced that science to determine that children are less culpable than adults and more capable of change — and therefore that sentencing a minor to an automatic life-without-parole term is an unconstitutional punishment.

That ruling draws a line applying the protection to those under 18, but Bret Grote, Lee's lawyer, argued before the panel, "That line faces in one direction." That is, it does not specifically preclude its application to youthful offenders who are 18 or older but possess similar attributes to a 16- or 17-year-old. He added: "We think a defendant whose crime reflects transient immaturity cannot be sentenced to life without parole."

Pennsylvania, which was home to more than 500 juvenile lifers when Miller was decided, has already resentenced the majority of them, some to terms as low as 13 years to life and others to life without parole all over again. But that relief has been limited to those who were 17 or younger at the time of their offense. For some, that meant months-long delays while lawyers hunted for birth certificates to determine whether a crime had occurred a few weeks before the lifer's 18th birthday, or a few weeks after.

The courtroom Tuesday was packed with people whose loved ones had just missed the cutoff, all hoping the hearing could be a turning point for a thousand or more other Pennsylvanians who were young adults but not legally minors when they committed crimes that led to life sentences.

Nadine Blackwell's cousin was in the process of being resentenced as a juvenile lifer, before a long-missing birth certificate revealed he was actually 18 years old when his crime took place.

Tracey Steele's husband, Herndon, was 21 when he was charged with a role in a fatal robbery. She says he wasn't involved in the crime, but just being around that crowd reflected his youthful immaturity. He's 53 now, though, older and wiser. "I was praying that they would open up the doors for everyone else. That's why I'm down here — to support her, but also the ones that are still left behind."

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In 2017, Superior Court dismissed Lee's case, but acknowledged the merits of its underlying argument: "It is hard to come away from an honest reading of Miller with the impression that arbitrary legal age of maturity is essential to Miller's rationale."

On Tuesday, the en banc panel expressed reservations about the limits of its authority in this case and the many procedural hurdles facing Lee, including time limits on post-conviction filings. President Judge Susan Gantman noted, "This case may be more appropriate for you to lobby your legislators. We are an error-correcting court, and we do not set policy."

But the judges also expressed concern that "someone a day over 18 and someone a day under 18 are treated differently," and suggested the matter deserved closer examination.

"What possible harm could there be in granting a hearing to develop the necessary facts so that we could knowledgeably look at the issue?" Judge John Bender asked, suggesting the possibility of at least granting Lee an evidentiary hearing.

"You're never going to have a factual record unless a trial court allows someone to put on a case," he added.

Judge Jack Panella suggested that advancing Lee's case might spur the legislature to review the issue: "Isn't it true that the legislature usually responds to issues like this when the courts raise them?"

But until now, many courts around the country — including Pennsylvania's Superior Court — have reviewed similar cases and rejected them.

A notable exception came out of a federal court in Connecticut, which in May granted the petition of Luis Noel Cruz, who was 18 when he participated in a gang-related execution. It relied in part on testimony by Temple University psychology professor Laurence Steinberg, who told the court that people under 21 "still show problems with impulse control and self-regulation and heightened sensation-seeking" — but that, like younger teens, they're also amenable to change.

In an email sent from the Cambridge Springs state prison, Lee described a grim early life that led up to the fatal robbery.

She grew up in poverty, a victim of sexual and physical assault starting at age 6, she said. Her parents were addicted, and at times sent her to buy heroin, she said: "I drank alcohol and used drugs to block the pain of these events out." By 17, she had dropped out of school and was working as a prostitute in downtown Pittsburgh.

Today, she said, she's changed her way of thinking. She works in the prison as a peer assistant in a drug and alcohol treatment program, and aspires to continue that work in society: "Pennsylvanians are dying from opioid addictions. I want to continue doing my part to fight this health crisis."

The Pittsburgh District Attorney's Office, in its briefings, questioned Lee's account: "The circumstances of appellant's crime do not reveal that it was the result of transient yet unfortunate youth."

Assistant District Attorney Margaret Ivory argued that the court need not go so far as to examine the facts of the case. "This is an error-correcting court, and that being said, there was no error. … As it stands, I believe the legislature has spoken on this."

The court could take several months to issue a decision — and either way, it's likely to be appealed to the state Supreme Court.

Marsha Levick, chief counsel of the Juvenile Law Center, which filed an amicus brief in support of Lee's case, said she and others will continue to litigate the issue.

"The judges recognize that there is an arbitrariness to the decision that the Supreme Court issued," she said. "Whether this will be the case that allows us to get past that arbitrariness, it's hard to know."