Trent Butt put his head in his hands and sobbed as his lawyer said Butt did not intend to kill his daughter — and that he does not remember doing it.

"He did not plan to kill Quinn Butt," said defence lawyer Derek Hogan.

Butt is facing first-degree murder and arson charges following the death of his daughter Quinn, who was found dead in Butt's fire-ravaged home in Carbonear on April 24, 2016.

He has pleaded not guilty to the charge.

In addition to the first-degree murder charge, Butt is also facing a charge of arson.

He initially pleaded not guilty to the charge, but as Justice Donald Burrage delivered his opening comments to the jury Wednesday morning in St. John's, he said Butt was now pleading guilty to arson.

Crown alleges a murder-suicide note was found

As Butt's trial began, Hogan said in his opening statements that Butt remembers kneeling over Quinn's body and concluding he had smothered her.

He said Butt then decided to kill himself and burn down the Carbonear home that he co-owned with his estranged wife Andrea Gosse.

His only failure in this murder-suicide plot was that he survived. - Crown attorney Lloyd Strickland

The Crown, however, presented a different portrayal of the events.

Prosecutor Lloyd Strickland said after the fire, there was a letter found in Trent Butt's truck which read, "I have taken my daughter's and my life."

He said Butt admits he wrote what the Crown called a "murder-suicide letter."

Strickland told the court that Butt killed his five-year-old daughter to punish Gosse "because he held such animosity towards her."

"He slashed his own wrist and neck and lay down in bed with Quinn," Strickland said.

Quinn Butt was 5 when she died at her father's house in Carbonear. (Facebook)

He said the sheets were soaked with gasoline.

"His only failure in this murder-suicide plot was that he survived," he said.

Strickland said evidence will show the coroner found the fire didn't kill Quinn and that she died before the fire started.

Family openly weeping

Family members from both Butt and Gosse's family were in court to hear the testimony. Many of them wept openly as the lawyers spoke.

Gosse will be the first witness called to testify this afternoon.

"This has been a long time coming," Gosse said outside the courtroom.

Andrea Gosse, the mother of Quinn Butt, has previously said 'it's hard to adjust without her. Quinn and I did everything together.' (Mark Quinn/CBC)

The Supreme Court trial is expected to take three weeks.

The jury — picked from an initial pool of 1,200 people — was sworn in Tuesday, after only two days of selection.

It was whittled down to 210, and finally to 14 jurors and two alternates.

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