A senior Liberal said the court decision would pave the way for Mr Harwin's return to cabinet. "Absolutely he can come back," the source said.

Another government source said Premier Gladys Berejiklian had opted not to give Mr Harwin's portfolios to another minister and assumed responsibility for the arts and special minster of state.

The source also said Mr Harwin was one of Ms Berejiklian's close friends and a confidant.

Mr Harwin was expected to appeal against the fine during a court mention on Friday, but it was dismissed shortly before 10.30am.

The hearing was not set to take place until October 28, after Revenue NSW advised no new court matters would be listed until October 1. However, it was brought forward following a special request by the Office of the Director of Public Prosecutions.

It is not clear why the hearing was brought forward in Mr Harwin's case, although an ODPP spokeswoman said it could "in certain circumstances take over and appear in summary proceedings".

Police had alleged Mr Harwin breached travel bans during lockdown by commuting between his Sydney residence and his holiday home.

He was subsequently handed the $1000 penalty infringement notice by NSW Police for being "in contravention of a current ministerial direction", against which he later lodged an appeal.

Mr Harwin resigned from cabinet soon after the infringement was issued. His ministerial responsibilities included the arts and Aboriginal affairs. He was also the special minister of state.

He has repeatedly insisted he did not break the law and returned to his Sydney home by March 31 when the Public Health Order formally began. The order restricted all non-essential travel without a "reasonable excuse."

He previously said he had been "working remotely" from his holiday home for "a number of weeks prior" to the Public Health Order coming into effect, and that he "took advice from my department officials about the Public Health Order to ensure I adhered to the guidelines during this period".

At the time he expressed regret that his residential arrangements had "become an issue" during the pandemic, but said he was "confident" he had acted in accordance with all guidelines.

"I apologise to the Premier and the people of NSW," he said in April.

In April The Sydney Morning Herald revealed Mr Harwin had decided to sell his Sydney apartment, just two weeks after he quit the cabinet.

The resignation resulted in a "significant pay cut" from his ministerial salary of about $345,000 to that of a backbencher's, which is approximately $170,000.

He remains a member of the NSW Legislative Council.