BALTIMORE (WJZ) — The recent arrest of a Baltimore teen connected to a brutal murder years ago is shedding light on the juvenile justice system.

A violent daytime attack on a man at the Mondawmin Metro station led MTA Police to the arrest of a teen who has been no stranger to authorities.

Prince Greene — who was charged as a juvenile in the murder of a Baltimore waiter two years ago — has been charged as an adult in another violent crime.

The case unfolded three months after Greene’s release from a juvenile detention.

According to our media partner The Baltimore Sun, Greene was picked up by police at the Cold Spring Station after being seen on video with a group of teens after the attack at the Mondawmin Metro.

Greene left a loaded gun on the train concealed in a backpack, according to The Sun.

In 2016, Greene and two others were accused in the murder of Robert Ponsi, who was killed while biking home from work.

“My son was stabbed, beaten and stomped,” Robert’s mother, Dawn Ponsi, said.

In charging documents obtained by WJZ, Greene confessed to the stabbing.

Greene being charged as a juvenile in the case was a decision that Dawn Ponsi said she pleaded with the judge to reconsider.

“He’s going to re-offend and, shockingly, under three months later, it’s coming to fruition,” she said.

Dawn Ponsi now wants a closer examination of the juvenile justice system that she says, generally, just provides a slap on the wrist.

“I just want to see a system put in place where you know it’s addressed accordingly. And right now, our system can’t address the most violent offenders,” she said.

Greene is due back in court later this month to face charges in this latest case.

WJZ also spoke with Greene’s mother, who said she wants her son to have a fair trial and wants all of the facts of the case revealed. She added that she feels her son is already being tried in the court of public opinion.

Follow @CBSBaltimore on Twitter and like WJZ-TV | CBS Baltimore on Facebook