Though Quintin hadn't had any scrapes with the law, Barbara Poindexter says she took a proactive approach. She sent him to the Mountain Manor treatment facility and the Victor Cullen Center.
David Miller, director of the Urban Leadership Institute in Baltimore, says that youths who get sucked into criminal activity do not always come from low-income neighborhoods. He said lack of fathers and glorification of violence is often a major factor.
"You have a lot of kids growing up in good families, doing everything they can to combat this nonsense, but there's some larger forces out here," Miller said.
Quintin's aunt, Robin Poindexter, remembers seeing her nephew fighting with an older man on the street. It was Williams, and he was teaching Quintin how to defend himself.
Robin Poindexter says she approached Williams.
"Is this something he's not going to be able to get out of, like a die-out thing?" she says she asked.
"He can walk away any time he wants to," she says Williams responded.
Quintin got a tattoo on his arm: "2900," a reference to the seedy apartment complex in the 2900 block of Garrison Blvd. where he was spending more and more time.
Barbara Poindexter would send his brother Gerard to find him and bring him home.
"I'd get up in the middle of the night, because he'd be in all kinds of different situations, more than I can remember," said Gerard Poindexter, 28. "The people he associated with lived in deplorable situations. … That apartment complex was a breeding ground for everything that had ill will and bad intent."
Quintin's first arrest came in November 2010, when a loaded handgun tumbled out of his waistband as he ran from police.
In August 2011, his brother found a gun stashed in the family couch, leading to a fight that ended with his mother taking out a protective order so her son could not return home.
In February 2012, Quintin was caught selling heroin in Southwest Baltimore.
Barbara Poindexter says her son had for the most part confined that activity to the streets. In her presence, she says, he was always contrite, even ashamed.
She says she never saw anything to suggest her son was in a gang, and would have rejected the assertion if someone else had made it. But she went digging through his things after his killing and found a Black Guerrilla Family rule book.
The surveillance tape from Windsor Hills shows three people involved in Quintin's killing. Detectives received tips that Williams was involved. In a search of his home, they found the murder weapon.
During questioning, police say, Williams gave the names of the other people with him that night. But no one has been charged or even questioned.
This upsets the Poindexter family.
"You had two black men that had records," Gerard said. "One died, and the other went to jail, and the case was closed as far as they're concerned.
"They do enough to get by, to quiet the families, to push ahead to the next case."