Australian Simon Gittany has been sentenced to 26 years in prison guilty, with a non-parole period of 18 years, for murdering his Canadian fiancée Lisa Harnum by throwing her off a highrise balcony.

Gittany threw Harnum to her death from the balcony of their 15th floor apartment in inner Sydney on a Saturday morning in July 2011.

New South Wales Supreme Court Justice Lucy McCallum, who presided over Gittany's judge-only trial last year, today also handed down his punishment. McCallum said that imprisoning Gittany for life would be excessive, but he has no prospects of rehabilitation.

Gittany's family erupted in courtroom

Gittany's family sitting in the court's public gallery erupted when she delivered the sentence.

"In the name of Jesus Christ, you won't be doing any of that time," one family member yelled. The judge ordered the family members to be removed from the court. During sentencing, McCallum described the cruelty of the crime.

Lisa Harnum

Lisa Harnum was thrown from her apartment balcony in the early morning hours of July 30, 2011.

"Ms. Harnum must have been in a state of complete terror in the moments before her death," she said. McCallum described Gittany as "arrogant" and said he had punished Harnum during their relationship for "small acts of defiance" such as wearing her hair down.

The court heard about Gittany's previous potential for violence, including an incident in which he bit off part of a policeman's ear in 1994.

"It has a troubling resonance with the present offence," McCallum said. The judge told the court that she had excluded evidence from a surprise prosecution witness last week — a former colleague of  Harnum who said Gittany had previously threatened to kill Harnum and make it look like suicide.

The businessman's current girlfriend, Rachelle Louise, who has fiercely defended Gittany and has been by his side for much of his trial, was not in court for the sentencing. Gittany himself was led up from the cells beneath the courtroom, but showed no emotion as he listened to the judge's comments.​

Outside court, his lawyer, Abigail Bannister, said there would be an appeal.

"Mr. Gittany does maintain his innocence and he does intend to appeal," she said.

Prosecution called for sentence of at least 20 years

The prosecution had called for a prison sentence of at least 20 years. Crown prosecutor Mark Tedeschi described Gittany last week as a cold and calculating killer who wanted to punish his Canadian fiancée.

The prosecutor questioned character witnesses provided for Gittany, telling the court the sentence should take into account an overriding community concern about domestic violence. Tedeschi said that Gittany was controlling and violent toward his girlfriend and had been aware she might leave him for some time.

He argued Gittany's intention all along was to kill his fiancée and make it look like suicide. The prosecutor told the court last week Gittany has prior convictions for drug-related offences and showed no regard for the safety of passers-by when he threw Harnum off their balcony.

Tedeschi likened it to "firing a gun during peak hour on George Street." Gittany's lawyer, Philip Strickland, had argued for a more lenient sentence, saying the 40-year-old was unlikely to reoffend.

Strickland told the court last week that Gittany has a "solid family," which would help his rehabilitation prospects. Gittany has always maintained he is innocent, describing himself as a "God-fearing Christian" who would "never kill anyone."