Eighteen jurors will be chosen from a pool of 350 in Harrisburg, Pa., because the case is highly publicized in Allegheny County, and brought to Pittsburgh, the Pittsburgh Post-Gazette reports.
The jurors are to be sequestered for the whole trial, which Judge Jeffrey Manning aims to wrap up by the end of June, with weekend sessions.
Poplawski is accused of killing officers Eric Kelly, Paul Sciullo II and Stephen Mayhle on April 4, 2009, after they came to his mother's home on a domestic dispute report.
Defense attorneys not involved in the case said conviction is almost certain and Poplawski's best hope is life in prison and avoiding execution.
"This case is not a whodunit," attorney William Difenderfer told the Pittsburgh Tribune-Review. "The defense doesn't have much. The facts are horrible. There's going to be photos, 911 calls and maybe evidence that shows after an officer was down, more bullets were pumped into him -- things that will rock a jury."
"It's just a horrendous fact situation," lawyer John Elash said.
Allegheny County District Attorney Stephen Zappala Jr. is seeking the death penalty.