Lavelva Merritt, 23, pleaded guilty to robbery and conspiracy to commit robbery in the stabbing death of a Johns Hopkins researcher in July, The Baltimore Sun reported. Her former lover, John Wagner, will be tried next month.
"If you do not cooperate, if you lie when you get on the stand, the state could go forward on the murder charges against you," Merritt's court-appointed attorney, William L. Welch III, told his client in a video recording of Wednesday's hearing in Baltimore Circuit Court.
If Merritt sticks to her story and is convicted, she will be sentenced to 30 years in prison, with 15 years suspended and three years on parole.
"It will probably be more like 10," said Charles Village crime watchdog Stephen Gewirtz.
Merritt said Wagner stabbed Stephen Pitcarin last summer and that she punched the victim in the face as he fell to the ground.
"We need to stop this revolving door in which violent criminals are arrested only to see their charges dismissed or spend a short period of time in jail and then return to the street to commit more acts of violence," Welch said.