During a hearing on Friday at the High Court of Australia, Justice Geoffrey Nettle faulted Mr. Newman’s decision to take the flight despite the revocation of his visa. “Acting as he did means he does not come to this court with clean hands,” Justice Nettle said, according to the Australian Broadcasting Corporation.

Peter Dutton, the immigration minister, said in a statement issued after the court ruling that he had told immigration officers to “expedite his removal.”

“His detention and removal is entirely related to his decision to openly flout Australian law and travel to Australia without a valid visa,” the statement said.

Terri Butler, a Labor member of the Australian Parliament, had called for the government to revoke Mr. Newman’s visa this week. In a letter to Mr. Dutton, she cited passages from a book that Mr. Newman co-wrote that called for abortion doctors to be executed.

On Friday, Ms. Butler praised the court’s decision.

“Here in Australia, we are a very open democracy,” she told reporters. “We have a lot of discussion, frank discussion, vehement discussion, about issues on which we disagree. And abortion is one of those things. But we don’t welcome extremists into our country.”