Internationally acclaimed Torres Strait artist Denis Nona has been sentenced to five years’ jail after being convicted of sexual assault which left a 12-year-old girl pregnant in the 1990s.

In December, an ACT Supreme Court jury found Nona guilty of all charges including raping the girl and exposing himself to the girl and her sister.

The crime came to light when the girl was found to be 20 weeks’ pregnant in 1996.

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But the victim never revealed that Nona was responsible until a DNA test strongly suggested he was the father.

It is the second time Nona has been found guilty of the crime, after he won an appeal for a retrial based on concerns about the instructions to the original jury.

Nona is already serving seven and a half years in jail after being found guilty of offences against the victim’s sister.

Nona’s total sentence for the crimes against the girls is now nine years.

Judge acknowledges Nona’s ‘difficult upbringing’

On Wednesday, Nona’s lawyer John Purnell complained to the court about the 10-year delay in charging Nona.

He said it was not as if he could not be found since he had sometimes sold art works to police officers.

Denis Nona in front of his winning art work titled Ubirikubiri in 2007. He won the $40,000 Telstra National Aboriginal and Torres Strait Islander Art Award

Chief Justice Helen Murrell acknowledged Nona’s Indigenous heritage and his difficult upbringing on the isolated Badu Island, where he suffered physical abuse in the form of what he termed “flogging”.

“The bright line that exists in Canberra between appropriate and inappropriate treatment of children did not exist when he was raised on Badu Island,” she said.

“None of this excuses the offenders conduct, but it does provide a context.”

Chief Justice Murrell told the court the assault which resulted in the pregnancy was particularly serious.

“The victim had to under go a significant medical procedure,” she said.

“The offence must have had a profound effect on the victim.”

But she said in the year’s since he appears to have rehabilitated himself.

“Not only has he not reoffended but he has embarked on a positive path making a contribution to Indigenous culture and Australian culture,” Chief Justice Murrell said.

Nona denies lying to court

Nona told the court he had been bashed in prison three times, but said he had not reported it because that would have made it worse.

“Sometimes you just want to go away from this world… hang yourself or harm yourself, but you have to be strong for your family,” he said.

“My culture is in me.”

But he told prosecutor Mark Fernandez his situation in prison was improving.

“Except at times like this when the media puts it out on the TV you can get attacked,” Nona told the court.

When challenged about incorrect evidence he gave the court which suggested he was not in Canberra at the time of one of the offences, Nona agreed it was not true, but said he was not lying.

“My aunty’s funeral was at that time and I was unstable… my mind was all over the place,” he said.

The court also heard from neuropsychologist Professor Warwick Brewer, who had assessed Nona.

Professor Brewer had given Nona a low intelligence rating, despite his academic success.

“His obvious talents as an artist had assisted him in the degrees,” he said.

“His visual, spatial and verbal skills appear to have declined with his significant use of alcohol.”

Nona had told him he did not remember having sex with the girls.

Nona will not be eligible for parole until 2017.

-ABC