Peter Figoski, a 22-year NYPD veteran (inset right), was shot and killed with an illegal semi-automatic weapon (inset left) while responding to a robbery in Brooklyn on Dec. 12, 2011.
One of five men accused in a botched robbery where an NYPD officer was killed is testifying against the others.
Ariel Tejada said Tuesday he starting robbing people at age 16.
The 23-year-old pleaded guilty and will receive a lesser sentence in exchange for his testimony.
NYPD Officer Peter Figoski was shot in the face on Dec. 12, 2011.
Prosecutors say the men planned to rob a drug dealer in Brooklyn but the police showed up.
Lamont Pride is accused of firing the fatal shot, but they have all been charged with murder.
Pride and the suspected getaway driver, Michael Velez, are currently on trial.
Two others are awaiting trial.
The men have pleaded not guilty.