Damian Leslie Harper: Jealous man jailed for attempting to murder wife and their two sons

A Tasmanian man who wanted to inflict “unbearable pain and anguish” upon his estranged wife, with plans to slit their children’s throats, has discovered his fate in court.

Harper was found guilty at a Burnie Supreme Court trial in February 2023 of three counts of attempted murder, plus wounding and aggravated burglary. Picture: File

It was early 2019 when Damian Leslie Harper armed himself with a stanley knife – determined to “inflict unbearable pain and anguish” upon his estranged wife.

Delusionally convinced his wife had been unfaithful, Harper planned to punish her with “an act of the utmost cruelty” – by murdering their two little boys.

He chose the day of their wedding anniversary to carry out his horrific crimes – a double murder and suicide thwarted by the “brave and desperate actions” of the boys’ mother and grandfather.

On Wednesday, the remorseless Harper discovered his fate after being found guilty of three counts of attempted murder, wounding and aggravated burglary by a Supreme Court of Tasmania jury in February.

He was jailed for 17 years, with a non-parole period of 11 years.

During the early hours of January 22, Harper drove from Bridgewater to Cuprona – a journey of three-and-a-half hours – with murder on his mind.

Cuprona, where Damian Leslie Harper, 48, attempted to murder his ex-wife and their two children. Picture: File

While sentencing, Justice Tamara Jago said he waited outside his wife’s parents’ home for almost five hours, walking around its perimeter to find points of entry.

Leaving a cricket bat, kitchen knife and multi-tool outside, Harper eventually climbed through an open window with the stanley knife.

He went directly to the bedroom where he knew his four-year-old and six-year-old sons were sleeping in their bunk beds.

He slit the throat of his four-year-old son, narrowly missing the carotid artery and jugular vein.

Harper then told his six-year-old boy, who was on the top level of the bunk, to come closer.

The two children began screaming, waking their mother who rushed in to save them and pull her estranged husband off one of the boys.

But Harper turned his attention on her, telling her “I’m going to kill you, you f … ing bitch”, stabbing her to the neck and back of her head.

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The boys’ grandmother arrived and coaxed the boys to safety, while their grandfather grappled with Harper – suffering a serious wound to his stomach in the process.

The grandfather pleaded with Harper to hand over the knife, which he did, before taking it back and attempting to slit his own throat.

Justice Jago said she was convinced Harper planned to murder his two sons to “inflict unbearable pain and anguish” upon his wife, amid his “distorted belief” that she had betrayed him on a work trip.

She said both his wife and youngest son needed surgery for their serious injuries to their necks – and that all three suffered ongoing psychological trauma.

Sadly, the boys’ grandfather died before the matter came to trial

“His bravery should be noted. But for his intervention, the end outcome may have been far worse,” Justice Jago said.

The judge described his premeditated murder plans as acts of the “utmost cruelty”.

“The defendant has shown no remorse for his behaviour, he has taken no responsibility for what happened,” she said.

“He continually blames his wife for what occurred.”

Justice Jago said experts found Harper had a personality disorder, but not mental illness, and was self-absorbed with a fragile sense of self and delusional jealousy.

He had become manipulative and controlling in the marriage, and asked his wife to take a lie-detector test after becoming fixated on her loyalty.

With time already served, the 48-year-old will be eligible to apply for parole in January 2030.