Her juvenile record was not available, but court records show that Hebron collected her first charges as an adult - for armed robbery in Annapolis - when she was 17. She spent a few months in jail before charges were dropped.
A year later, in February 2004, an Annapolis officer spotted Hebron gassing up a stolen Dodge Stratus. She was convicted and sentenced several months later to time served.
Hebron's propensity for violence became apparent in October 2004. Stokes saw Hebron in the Robinwood public housing complex and, knowing she'd been banned from the property, approached to arrest her.
She ran, he grabbed her arm, and the two struggled and fought as Hebron kept reaching for her back pants pocket. Stokes found out later that she'd been reaching for a loaded .22-caliber revolver.
The officer finally handcuffed her. On the drive to the police station, Hebron kicked at the rear windows and yelled and cursed, screaming to Stokes that she'd find him and kill his children.
"It's a day I'll always remember," Stokes said in a recent interview. "She's one of the toughest people I've ever arrested."
Hebron remained combative in jail. When a correctional officer escorted her to her cell, she dropped to her knees and spat on the guard through a food slot, according to court documents, leading to a second assault charge.
She was convicted in both cases. In her 2 1/2 years in prison, she wrote at least three letters to Anne Arundel Circuit Judge Joseph P. Manck, asking him to consider releasing her.
"I must say your choice of sending me to prison was wise," she wrote in July 2005. She talked of taking the GED test, enrolling in anger management classes and attending prison church services. "I am preparing myself to be productive in society for a change."
Hebron was released April 17, 2007, but she was far from changed, authorities say. Within six weeks, she had written a letter to Willock, the alleged top boss of Tree Top Piru, telling him she expected to be appointed the gang's Annapolis leader.
Fresh out of a Jessup prison, Hebron traveled 72 miles to Hagerstown, moving to a homeless shelter and then to an apartment in a downtown house. Other indicted gang members, including Willock and his girlfriend, also have ties to the Western Maryland town.
Federal authorities believe Hebron traveled between Hagerstown and Baltimore several times last summer, including to a July gang picnic in Carroll Park.
Then, on Aug. 11, a man that gang members believed to be cooperating with police was shot in South Baltimore. Witnesses put Hebron at the scene, and one person watched her shoot the man, Assistant U.S. Attorney Steven H. Levin said at Hebron's detention hearing. Charges in that case have not been filed.
Back in Hagerstown, in the foyer of Hebron's apartment house the afternoon of Oct. 5, David Leonard Moore was fatally shot in the head at close range, police reports state.
That's when Detective Andrew Lewis called the Annapolis police to ask what officers there knew about Hebron. Stokes, who knew first-hand how violent Hebron could be, answered the phone.
"That call brought her up on our radar screen," said Lt. Mike King, supervisor of the Hagerstown Police Department criminal investigations division.
Soon after, a witness came forward and identified Hebron, King said, and within five days of the killing she was under arrest and charged with murder. (State charges were dropped last month to allow federal authorities to take over the case.)
A search of Hebron's apartment found a 32-line poem laced with profanity and gang slang, including a reference to the Bloods' signature color. It begins: "Red robins flyin round my/ head [racial slur] goin' crazy I/ guess just shot a [racial slur] in the head cause he wear blue but claim red."
Reflecting on his interaction with Hebron, Stokes said, "Some people can be rehabilitated, but Michelle Hebron - I don't think she can. I think she'll be a violent person her whole life."