A disgraced former Navy commander will spend the next two years in jail and 15 years listed on a child sex offender register after he was found guilty of seven child sex offences.

Key points: David Graham, 50, was found guilty of three counts of indecent dealing with a child under 10 years, three acts of gross indecency and attempted sexual intercourse

David Graham, 50, was found guilty of three counts of indecent dealing with a child under 10 years, three acts of gross indecency and attempted sexual intercourse One victim said Graham's predatory abuse had caused him ongoing psychological problems

One victim said Graham's predatory abuse had caused him ongoing psychological problems Graham did not express any remorse or concern for his victims, and did not accept any responsibility for his actions, the judge found

David Graham, 50, was found guilty of inappropriately touching two young boys in Darwin between 2006 and 2008, as well as attempting to rape one of them while camping near Alice Springs.

Justice Graham Hiley sentenced him on Tuesday in the Supreme Court in Darwin to five years behind bars, to be suspended after two years.

Abuse had extreme effects on victims

The sexual abuse had extreme impacts on the two victims, who are now young adults, with both suffering mental health issues and one even attempting suicide, the court heard.

"I became withdrawn, anxious, and scared about what people would think about me," one victim said in a statement.

"I felt like I couldn't do anything about it."

The man, who cannot be identified, also wrote directly to his abuser in his statement to the court.

"You and I, and now the world, know that you are guilty. I hope you see through your lies and realise that until you admit your guilt, you can't be helped," he wrote.

The younger victim, who saw Graham as a "father figure", told the court the reality of the abuse didn't sink in until he reached puberty.

"My belief is that Graham is solely to blame for not only the turmoil I faced as a child or the delinquent I became throughout puberty but also the mental instability I face," he said.

Boys idolised and trusted senior naval officer

The court heard that Graham did not 'express any remorse' for his crimes. ( ABC News: Al Dowler )

"I believe that he should pay for every drink that I've had past moderation, every suicidal thought that has ever entered my head, every sleepless night I had as a child, and for every day of my life that I have to bear the knowledge that I was a victim of sexual assault.

"The predatory and sexually abusive actions of David Graham have undoubtedly been the cause of the immense emotional and psychological damage that continues to wreak issues within my psyche today."

The court heard Graham's abuse of the boys was "opportunistic" and despite only being charged with seven offences, he had abused them "at least" 10 times.

Graham did not display emotion as he sat in the dock as Justice Hiley read out his sentencing remarks.

"Your conduct is particularly serious. Firstly, both of your victims were vulnerable," he said.

"[The younger victim] idolised you, he permitted you to do these things to him, even though he knew what you were doing was wrong.

"You knew the parents had complete trust in you … it was also based on trust in you in your capacity as a senior naval officer. You breached that trust and abused your power over those boys."

Offender expressed no remorse, responsibility

Graham's barrister, Tom Berkley, told the court he'd been "embarrassed" by the media attention his trial received, and that Graham was otherwise a man of good character.

Justice Hiley found the offending was in the "middle" range of seriousness for child sex offending.

"You do not express any remorse, you have not expressed any concern for your victims, and you do not accept any responsibility for your conduct," Justice Hiley said.

"Because of your denials, your victims had to be strongly challenged on their evidence."

Graham will be released from prison in August 2021.