ST. JOHN'S, N.L. -- A jail guard who spilled Nelson Hart's lunch on the floor in a clash that ended with Hart being hauled to segregation with his pants around his ankles denies that he targeted him.

Hart was imprisoned in St. John's, N.L., on June 24, 2013, pending an appeal of a murder conviction in the deaths of his three-year-old twin daughters.

He was in provincial court Wednesday for a judge-alone trial on three charges of making threats and one count of mischief to property.

Ryan Preston, a correctional officer at Her Majesty's Penitentiary, was one of eight guards who swarmed Hart in his cell as he lay on his bunk. They were responding to a "code yellow" emergency call for backup staff.

Hart had swung a kettle into a wall-mounted television outside his cell after Preston spilled his lunch then gathered other food not allowed in his cell.

Preston testified the dispute started when Hart refused to put on his shirt before a meal as required under jail policy. He denied that he or any other guards hit Hart or insulted him during the altercation shown in court on silent surveillance video.

Preston testified that Hart repeatedly threatened to kill the guards. He said Hart also refused to get off his bed and come to the wicket in his cell door to be handcuffed before the officers went in.

"Cell extraction" policy calls for a minimum of six officers, he explained.

"He was restrained due to fear of him assaulting us."

Hart, 46, frequently shook his head or looked skyward as Preston testified.

Under cross-examination, the guard confirmed that Hart had repeatedly complained of mistreatment by Preston but said those were all false allegations. Preston also said he had written up Hart for various internal infractions.

Defence lawyer Jeff Brace pointed out on the video how another inmate was eating shirtless as guards ordered Hart to put his on.

"There clearly is a difference," in how his client was treated, Brace said. He also questioned the credibility of internal reports filed after the incident by Preston and another guard, Krista Williams.

They submitted reports that were identical except for where one substituted the other's name, Brace said.

"They got their stories straight," he said.

Stephen Woolridge, another guard, testified he grabbed Hart from behind after he threw the kettle.

"That's pretty much as threatening as it gets when it's paired with verbal threats," Woolridge said.

Woolridge denied he shoved Hart into a wall as he was heading back inside his cell, as the video suggests.

"We controlled him into the wall."

A police officer who interviewed Hart two days later said he had purple bruising on his left shoulder, both upper arms and scratches behind his left ear. Const. Matthew Dixon told court Hart said one of the guards punched him and told him to "squeal like a pig."

Hart was released from jail last August after the Crown said it lacked enough evidence to retry him for first-degree murder in the 2002 drownings of his daughters at Gander Lake.

A Supreme Court of Canada ruling last July concluded confessions Hart made to undercover police posing as gangsters were inadmissible.

The trial continues May 15.