Nelson Morales, 29, was on trial for leading the five-man crew in the attempted robbery of a drug dealer in Brooklyn in December 2011.
One of those men, Lamont Pride, fatally shot Officer Peter Figoski as he tried to flee the robbery in the Cypress Hills section.
Morales was convicted of second-degree murder and burglary.
It is the second trial connected to Figoski's death. The first ended with Pride being sentenced to 45 years to life in prison.
A verdict has not yet been read for suspect Kevin Santos.
Figoski was posthumously promoted to detective.