The perjury trial of state Sen. Robert Regola III opened this morning with Westmoreland County District Attorney John Peck telling jurors that the legislator made contradictory statements about where a gun was stored that a teenage neighbor used to commit suicide.

During his 35-minute opening statement, Mr. Peck said Mr. Regola testified last year during a coroner's inquest -- an official proceeding -- that his handgun was never kept in the room of his son, Bobby.

However, the district attorney told jurors, Mr. Regola had earlier told police that the gun had indeed been stored in Bobby's room until the senator grew concerned about reports of area vagrants and moved it to his own bedroom.

Mr. Regola, 45, a Republican from Hempfield, is charged with three counts of perjury, false swearing, allowing possession of a firearm by a minor and reckless endangerment stemming from the July 2006 death of Louis A. J. Farrell, his 14-year-old neighbor.

Louis was dog-sitting for the Regolas while the senator was out of town when he committed suicide with Mr. Regola's 9 mm pistol.

Defense attorney Charles Porter Jr. used his 20-minute opening statement to tell jurors that no perjury was committed. Instead, he said, there was merely a disagreement over recollections by the senator and state police investigators.

Police did not keep any notes or make a taped record of their interview with Mr. Regola, Mr. Porter said. He added that investigators never showed Mr. Regola their notes or read them to him.

"It's almost as if they were setting him up," Mr. Porter said.

As for the charge of reckless endangerment, Mr. Peck said Mr. Regola did not call police to report a stolen gun as soon as he learned from his son by phone that the firearm was missing. He also did not call the Farrell family despite knowing that Louis had been in the house that day.

Bobby Regola had remained in Hempfield while his father went to Harrisburg, but he spent the day at an amusement park and returned home late in the evening to find the missing weapon.

Mr. Porter countered by saying that the senator had no reason to think that Louis had stolen the gun, that the teenager never showed a fascination with guns, and that he was a trusted family friend.