Unflinching, John Lang sat and stared ahead as an Allegheny County jury rendered its guilty verdict against him for first-degree murder.

A few minutes later, he declined to speak and maintained a blank expression as Common Pleas Judge Jill E. Rangos sentenced him to consecutive life sentences without parole for killing his wife and a man he suspected was her lover.

Mr. Lang, 35, shot Tracy Braverman-Lang, 41, and Louis Goldenson, 37, after coming upon them outside Don Pablo's Mexican restaurant in Monroeville. He then called 911 and calmly admitted the crime, detailing his actions to investigators.

The Pitcairn volunteer firefighter kept the stoic demeanor during the two-day trial and sentencing.

"No emotion; no sadness; no 'I'm sorry,'" said Gilbert Braverman, 69, Ms. Braverman-Lang's father. "He got what he deserved. I just hope he has a hell of a hard time in prison."

Mr. Lang's attorney, Bob Foreman, who called no witnesses, argued that the crime was committed in the heat of passion, as Mr. Lang witnessed his wife in the embrace of another man. He asked jurors for a verdict of voluntary manslaughter.

"Being confronted, right in front of your own face, with a cheating spouse -- of course that's going to dramatically affect you," Mr. Foreman said in his closing argument.

Explaining Mr. Lang's coolness after the shooting, Mr. Foreman said, "We are talking about a firefighter. In a crisis, they're not expected to lose their composure."

Deputy District Attorney Bruce Beemer argued that Mr. Lang was mistaken when he said he saw the two victims kissing. They had been friends since childhood, according to witnesses, and nothing more.

And though Ms. Braverman-Lang had lied to Mr. Lang about who she was with -- saying she was consoling a cancer-stricken girlfriend -- she told him she was at Don Pablo's. The couple was having marital difficulties, and Ms. Braverman-Lang just wanted some time alone with a friend, Mr. Beemer said.

"If she was going to have a cheating affair with Louis Goldenson, why would she tell [Mr. Lang] where she was going?" Mr. Beemer said.

When Mr. Lang arrived at the scene, he rolled down the window, said "Hi" and drew his gun. He shot both victims twice, then parked the car and shot them each again in the head and chest, showing the deliberate and premeditated nature of the crime, Mr. Beemer said.

Referring to the 911 call, the prosecutor said, "You would have thought [Mr. Lang was] ordering a pizza. It was that passionless. It was that controlled."

The defendant's calm was contrasted with the tears of the victims' families and friends, who said they were pleased with the verdict.

The victims grew up near each other in the Garden City section of Monroeville, and their families have been friends for decades. Both victims and Mr. Lang were part of the close-knit volunteer firefighter community.

Sabrina Orlansky, Ms. Braverman-Lang's friend who also testified at the trial, was the only representative of the victims to speak in court before Mr. Lang was sentenced.

"Three families have been destroyed," she said.

"More than that, he destroyed a community."