Stephen John Ellis, a former journalist and senior NBN adviser to Mr Turnbull, was arrested after an alleged act of indecency committed in the presence of another man.

ACT police arrested Ellis, 47, and held him in custody overnight. He appeared in the ACT Magistrates Court on Friday morning, represented by barrister James Lawton.

Ellis' mental health was assessed following the airport incident.

The results of the test are unknown, but a mental health consumer assessment was made available to the court.

Mr Turnbull issued a short statement late on Friday, saying Ellis had resigned from his office.

"As this matter is both very personal and before the Court I have no further comment to make," he said.

Ellis also issued a statement, saying he would address the charges through the normal legal process.

"Earlier today I resigned as a government staff member following my appearance in the Canberra Magistrates Court," he said.

"On legal advice, I will be making no further comment at this time."

Earlier on Friday, Prime Minister Tony Abbott was asked if Ellis should continue working for Mr Turnbull.

"It is a private matter and I don't propose to comment on something which is almost certainly coming before the courts," he told reporters.

"I guess I just make general point that when people have personal issues, they should be given all the support and all the encouragement that they possibly can to work through those issues."

Ellis said nothing during the brief court appearance on Friday, and made no comment to reporters outside court.

Mr Lawton also made no comment on his client's behalf.

Prosecutors did not oppose Ellis' release on bail, but asked for conditions that he reside at an address in Sydney, and not consume illicit drugs.

Magistrate Bernadette Boss formally charged Ellis with two possession offences, offensive behaviour, and committing an act of indecency in the presence of another.

Ellis will reappear in court early next month.