Updated

A Detroit police officer is defending his decision not to arrest a murder suspect on the street a few hours before an unsuccessful attempt to catch the man led to the fatal shooting of a 7-year-old girl.

Raymond Trammell says he was sitting alone in an unmarked car when suspect Chauncey Owens walked by. He says it would have been extremely dangerous to try to arrest Owens and would have violated policy for officers on surveillance.

Trammell testified Wednesday in the trial of a fellow officer, Joseph Weekley. Weekley's gun accidentally fired during a raid to capture Owens in a Detroit house, killing Aiyana Stanley-Jones in May 2010.

Weekley is charged with involuntary manslaughter. The jury is expected to hear from a key witness, Aiyana's grandmother.