Attorney General William Barr met last year with media mogul Rupert Murdoch to pressure him to muzzle Donald Trump critic Andrew Napolitano on Fox News , according to a new book out Tuesday.

Napolitanos air time has dwindled as his criticism of Trump has increased over the last year.

Barrs meeting with Murdoch, the executive chairman of Fox News parent company, at his New York home was widely reported at the time, but its purpose was not revealed. One aim of the meeting was to shut up Napolitano, according to the book Hoax: Donald Trump, Fox News , and the Dangerous Distortion of Truth, written by CNN media reporter Brian Stelter .

Trump was so incensed by Napolitanos increasingly critical comments about him in Fox News broadcasts that he implored Barr to send Rupert a message in person about muzzling the judge, according to the book, reported The Guardian, which obtained a copy. Trump wanted the nations top law enforcement official to convey just how atrocious Napolitanos legal analysis had been, wrote Stelter, citing information from an unnamed source.

Napolitano, a former New Jersey superior court judge, reportedly told friends early in 2019 that he was on Trumps short list for the U.S. Supreme Court . But when news emerged later that year of Trumps phone call pressing Ukraines president to launch an investigation into baseless accusations against Joe Biden , Napolitano called the presidents actions both criminal and impeachable .

The judge also said that much of what was found in an investigation by former special counsel Robert Mueller concerning Russian interference in the 2016 election was also impeachable .

Barrs words carried a lot of weight with Murdoch, Stelter reports, though its unclear how the pressure to silence Napolitano served taxpayers funding Barrs salary.

A daytime slot for Napolitano soon disappeared and he was carved out of coverage of Trumps impeachment, Stelter noted.

Fox Business host Maria Bartiromo would only book Napolitano to discuss non-Trump topics, because she would become too upset when he criticized Trump, a staffer told Stelter.

Napolitano still appears on Fox News, though in a more limited role. He recently harshly criticized Trump for sending federal officers into Portland to snatch residents off the streets, calling it a dangerous slide into totalitarianism . There is nothing lawful or orderly about the aggressive tactics Department of Homeland Security officers are wielding against people protesting racism, he wrote in a Fox News opinion piece. The agents actions are unlawful and unconstitutional, he wrote.

He has also blasted Barr as Stalinistic.