Darko Desic, 64, was homeless when he walked into Dee Why police station and confessed to breaking out of a Grafton jail on the state's north coast on the night of July 31, 1992.

He has pleaded guilty to escaping from lawful custody and was returned to prison where he is serving the rest of his original jail term for supplying marijuana.

Desic would be eligible for parole on November 1 next year.

His lawyer Paul McGirr said he had written to the attorney-general and the governor-general seeking clemency, but noted the matter could drag out due to it being "quite convoluted".

One of the difficulties posed was the change in sentencing principles, Mr McGirr told magistrate Jennifer Atkinson in the Central Local Court on Thursday.

"You can't sentence him to 100 days' hard labour which might have been available back then," he said.

Desic had not committed a single crime while "on the run," and was essentially serving outside another sentence with the guilt hanging over his head.

"Not knowing when someone will knock on the door ... someone coming across the sand dunes to arrest him," he said.

Mr McGirr said his client had led a blemish-free life for three decades, had never entered an RSL club, had no Medicare card and had removed his own teeth.

The court was told Desic fled prison to avoid being sent back to the former country of Yugoslavia where he was due to serve on the frontline of war.

The northern beaches community where Desic has since resided "love and respect" him so much a crowdfunding campaign has raised $30,000 in support of him, Mr McGirr said.

"He still has the attitude he did the wrong thing and is prepared to serve a sentence if the court deems it appropriate."

Prosecutor Scott Williams said the case evoked a "romantic idea" of escape from custody and the fact remained Desic had been at large within the community avoiding his return.

A full-time custodial sentence was necessary to ensure other inmates contemplating breaking out knew they would be punished "no matter how long after escape when captured," he said.

"There's a strong need to denounce the conduct of this offender," he said.

Desic was jailed in 1990 for drug supply, serving 19 months of a 33-month minimum term until his escape, allegedly done with a hacksaw blade and bolt cutters.

He faces another prison sentence of up to 10 years due to laws at the time of his escape.

The judge is due to hand down her sentence later in the day.

Australian Associated Press