(CNN) -- Witnesses began describing the final moments of and futile attempts to save a Connecticut mother and her two daughters inside their burning home, opening the trial Monday for one of the men who authorities claim is responsible for their murders.
Prosecutors declined to give an opening statement to start the trial of Joshua Komisarjevsky, 31, who faces 17 charges in a brutal home invasion in Cheshire. But they did introduce tapes from two 911 calls, a bank teller who claimed the mother tried to withdraw $15,000 as ransom and a police officer who found Dr. William Petit -- the lone survivor -- fighting for life outside his family's burning home.
The first defendant to stand trial in the case, Steven Hayes, was sentenced to the death penalty in December after being convicted on 16 of 17 charges filed against him.
Prosecutors allege that Hayes and Komisarjevsky went into the Petit home, beat and tied up Dr. William Petit, raped and strangled his wife, molested one of their daughters and set the house on fire before attempting to flee.
The two daughters, who were both tied to their beds, died of smoke inhalation. William Petit managed to escape.
Entering the New Haven court Monday, Petit succinctly told reporters, "I just hope justice was served." He was one of several of the victims' family members packing the courtroom, many of them wearing pins that Judge Jon C. Blue allowed over defense lawyers' objections they might sway the jury.
While he didn't present a comprehensive statement, New Haven State's Attorney Michael Dearington briefly spoke to jurors, explaining that prosecutors believe the jury will be able to listen to the evidence and render a decision. Under the law, Dearington said, Komisarjevsky is charged both as a principal and an accessory.
Komisarjevsky's defense attorney, Walter Bansley, told jurors that his client never intended to kill anyone, that his sole purpose in breaking into the Petit home was to steal.
Bansley said Komisarjevsky did not have a weapon. He told jurors that in order to convict Komisarjevsky of capital murder, they must determine he intended to kill someone.
It was Hayes, Bansley said, who raped and strangled Jennifer Hawke-Petit, poured the gasoline and lit the match. Komisarjevsky was a willing participant in the break-in and theft, but not the murders, according to Bansley, who recounted mounting dissension between Hayes and Komisarjevsky as the home invasion progressed through that morning.
Hayes felt the Petits needed to be killed, Bansley claimed, but Komisarjevsky refused to kill anyone.
Bansley did allude to a "confession" that Komisarjevsky had later made in the incident. While it was not yet entered into testimony on this trial's first day, during Hayes' trial, a court clerk read from writings of Komisarjevsky, in which he described the incident in a 40-page letter that he wrote to author Brian McDonald in 2008.
"All were compliant," he wrote. "This time I took a risk, pulled the trigger, and the chamber was loaded. ... The Petit family passed through their fears and into terror.
"... It was captivating, validating that this pain in me was real. ... I was looking right at my personal demon, reflected back in their eyes. ... Hayley is a fighter; she tried time and time again to free herself. ... Mr. Petit is a coward; he ran away when he thought his life was threatened, and ran away to leave his wife and children to madmen. ... I was cheated of my retribution, and so was Steve. ... I am what I am; I make no excuses. ... I'm a criminal with a criminal mind."
The reading continued, "Michaela, Hayley, and Jennifer, forgive me; I am damned. ... I can't believe I lost control; I hate myself/I love myself. ... I stand condemned."
After the defense lawyers presented their opening arguments, the prosecution began to present evidence and call witnesses -- the same five people thus far, in the same order, as they did during Hayes' trial. If they continue this trend, Dr. Petit would be the next witness to testify when the trial resumes Tuesday morning.
The first person on the stand Monday was Mona Huggard, a registered nurse at Petit's medical practice who said that Hawke-Petit had called in to say her husband was sick -- only the second time, in her recollection, that he'd ever done so.
Then Kristen Makhzangi testified how Hawke-Petit came to her bank window to withdraw $15,000. Video showed the transaction, which spurred a 911 call from the Bank of America branch's manager, Mary Lyons, warning that that the family might be in trouble. Lyons described Hawke-Petit as "terrified." About an hour after the visit, authorities say, she was dead.
Another 911 call came from the Petits' next-door neighbor David Simcik, who testified spotting Dr. Petit "all banged up" and asking him to call police.
And lastly on Monday, Cheshire Police Office Thomas Wright explained how he'd arrived to find Petit bloodied on his neighbor's driveway.
By the time he tried, unsuccessfully, to enter the door of the home, Hayes and Komisarjevsky had left and "everything was burning," Wright said. Authorities threw rocks at windows and doused flames with a nearby hose.
But once they finally got in, "We saw no signs of life," he said.
In Session's Sunny Hostin and CNN's Deborah Feyerick contributed to this report.