With stunning hypocrisy Newt Gingrich slammed FOX News anchor Megyn Kelly Tuesday night for, in his view, putting prurience ahead of public policy in her coverage of the U.S. presidential race.

Gingrich scolded Kelly for framing her question about Donald Trump's nosedive in opinion polls around whether the Republican nominee is a sexual predator.

She simply wanted to know whether the uncovering of a tape of Trump making lewd comments about women a few weeks ago was a turning point in the campaign, but Gingrich was having none of it.

"You are fascinated by sex and you don't care about public policy," he said.

Then he accused Kelly of a double standard.

"I just want to hear you use the words 'Bill Clinton, sexual predator.' I dare you. Say, 'Bill Clinton sexual predator!'"

Kelly didn't say those words, possibly because of a double standard but probably because of legal risks.

She might well think both Trump and Clinton are sexual predators, but the fact is only one of them has confessed on videotape that he grabs strangers by the genitals and pops Tic Tacs in his mouth in case he decides to force his lips on a woman.

WARNING: This video contains graphic language

Gingrich's bizarre pretense that he's a policy guy who floats above the unseemliness of character investigations is, however, a howler.

It's a pose he's struck before.

In his 2012 run for the Republican nomination, he deflected a question from CNN anchor John King about his ex-wife Marianne's much-publicized allegation that Gingrich had proposed they agree to an "open marriage" after he admitted he'd been having an affair for the past six years.

"I think the destructive, vicious, negative nature of much of the news media make it harder to govern this country, harder to attract good people to run for public office," Gingrich lectured King to wild applause from the Republican audience at the all-candidates debate.

"And I would be appalled that you would begin a presidential debate on a topic like that."

Newt Gingrich reacts angrily to a question at the start of the Republican presidential candidates debate in Charleston, S.C., back in 2012. (Associated Press)

Somehow whenever he has something scornful to say about the devolution of America's political discourse, Gingrich's accusing finger always seems directed at the news media.

Yet Gingrich was at the scene of the original sin when the boundaries of investigation into character and sexual behaviour in political life were erased. In fact, his fingerprints are on the eraser.

Gingrich was the Speaker of the House when President Bill Clinton was impeached.

Politically motivated digging

The charges against Clinton were that he had perjured himself and obstructed justice. But the facts of the case — that he lied to cover up his affair with a White House intern, Monica Lewinsky — only came to light through years of digging through the muck of Clinton's sexual past.

It's well documented that the digging was politically motivated. It began as an investigation into Clinton's business dealings when he was governor of Arkansas and somehow spread to every corner of his private life, including accusations of sexual harassment, sexual assault and ultimately to the Lewinsky affair.

For months, the news overflowed with accounts of who touched whom, where and when.

In the course of that the details of Clinton's private parts were subject to investigation, described for the record and flushed out on cable news to saturate the country.

Hillary Clinton called it "a vast right-wing conspiracy" against her and her husband and there is evidence to support that. She also took a hands-on approach to her husband's defence and went along with the character assassination of his accusers as "nuts and sluts."

First lady Hillary Rodham Clinton watches President Bill Clinton pause as he thanks those Democratic members of the House of Representatives who voted against impeachment in this Dec. 19, 1998, file photo. (Susan Walsh/Associated Press)

There is no argument that much of Bill Clinton's conduct was deplorable. He lied under oath, but also to his wife and to his closest friends and colleagues. Some of the most serious allegations of his behaviour toward women persist to this day.

His behaviour fed the media hunger for sleaze, no doubt. But changing attitudes and standards worked against him, too.

Feminists and evangelicals unite

The 1990s was a time when two ideologically divergent social and political movements found a common purpose.

Feminists and evangelicals, for different reasons, both agreed that the character of political office holders — their private behaviour — should matter in public life.

As Jeffrey Toobin writes in his book A Vast Conspiracy, feminists insisted "the personal is political" just as Christian conservatives began asserting the motto "Character Counts."

And therein lay a political opportunity for Republicans.

There is no doubt Clinton's fiercest opponents wanted the impeachment so they could put his character on trial and House Speaker Gingrich was their instrument.

In the midterm elections of 1998, Gingrich lent his then-considerable influence to making the impeachment of the president the Republican's central campaign issue.

Backfire

But he badly misread the mood of the country and the tactic backfired spectacularly.

Democrats held the Senate and made gains in the House in a year when the historical pattern indicated the opposite should have happened.

Soon after the election, Gingrich resigned as Speaker. Then his expected replacement, Robert Livingston, withdrew from consideration for the office amid revelations of an extramarital affair.

The impeachment of Clinton proceeded and he was acquitted in the Senate.

But the private sex life of public figures became a permanent concern of American political discourse.

Nearly 20 years later, Gingrich still bemoans the media fascination with sex over policy in one breath and in the next says to Megyn Kelly: "I just want to hear you use the words 'Bill Clinton, sexual predator. I dare you. Say, 'Bill Clinton sexual predator.'"

She suggested he work on his anger issues instead.

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