PITTSBURGH (AP) - The trial of a Pittsburgh man charged with shooting three city police officers to death during a standoff has been postponed until June because a defense expert witness was injured.

Allegheny County Judge Jeffrey Manning delayed jury selection Thursday to June 6, with testimony to begin June 20.

The trial of 24-year-old Richard Poplawski had been scheduled to begin in April, but the judge delayed it after learning that a key defense witness was hurt in a bicycle accident and had to have surgery.

Poplawski faces the possible death penalty if he's convicted of killing the officers who answered a domestic dispute call from his mother in April 2009.

The jury will be selected in Dauphin County and bused to Pittsburgh for the trial.