In a stunning revelation of journalistic duplicity, the New York Times reports:

Even though Mr. Gingrich publicly insists that he will take the high road with a positive campaign that does not criticize other Republicans, he recently strayed from that vow, offering himself as an anonymous source in a New Hampshire newspaper last week to reply to criticism by John H. Sununu, a former aide to President George H. W. Bush who, as a Romney surrogate, has called Mr. Gingrich “untrustworthy and unprincipled.”

Mr. Sununu told the newspaper, the Union Leader, that Mr. Gingrich supported a tax increase deal that the first President Bush made with Democrats in 1990, then reversed himself. The newspaper, quoting a source identified as “a senior aide in the Gingrich campaign,” elaborately rebutted this account.

[R.C.]Hammond [Gingrich spokesman’s] said the source was actually Mr. Gingrich, who did not want to be identified to avoid the impression he was getting into a fight with the Romney camp.

The original Union Leader story quoted Sununu recounting Gingrich’s about-face in privately supporting and then publicly opposing the George H.W. Bush deal that violated the “read my lips, no new taxes” pledge. The Union Leader included this:

He said the White House had assured Gingrich and [chief Senate GOP negotiator Phil] Gramm “we would not accept any agreement they did not support.”

A senior aide in the Gingrich campaign said Gingrich’s position was that he was consistently opposed to new taxes and that he “had said consistently to Sununu and (former Office of Management and Budget Director) Dick Darman that he would not support a net tax increase.”

The aide said that “things were represented to Gingrich in the afternoon that, when checked, turned out not to be accurate. There was a net tax increase, and the Republicans didn’t get the things they were told they were going to get.”

Sununu said Gingrich was clearly aware of the tax increases included in the plan when he agreed to it.

The Gingrich aide said Bush’s 1988 no-new-taxes pledge had “thrilled” Gingrich, who believed it fueled the Republican enthusiasm that sent Bush to the White House.

But, the aide said, Gingrich was “shocked when the President was forced by the Democrats to back off that commitment in the summer of 1990.”

The Gingrich aide said that the morning the budget agreement was to be announced and the key players gathered in the Cabinet room of the White House, “Gingrich stayed with the Bush 1988 pledge of no new taxes and said, with sadness, that he could not agree to go along with the tax increase. He was the only person in the room to say that.

“When all the rest of them trooped into the Rose Garden, Gingrich walked out the front door,” the aide recalled.

The aide also noted that Gingrich “clearly represented the majority of House Republicans because in the vote, an overwhelming majority voted against the tax increase.”

I contacted the reporter and Joe McQuaid, the outspoken Union Leader publisher who recently endorsed Gingrich. I asked a series of questions: Is the New York Times story accurate in reporting that you allowed Gingrich to speak as a senior aide in rebutting statements by John Sununu? Was this misleading to readers? R.C. Hammond [a Gingrich spokesman] says Gingrich did this to hide the fact he was engaging Romney. Should the Union Leader have assisted in this effort? Does the Union Leader have guidelines for unnamed sources? Do you owe readers an apology? Was your cooperation influenced by the Union Leader’s decision to endorse Gingrich?

The reporter wasn’t allowed to respond But McQuaid e-mailed back. “Thanks for alerting me to the NY Times piece. Not sure about the Times, or the Post, but the Union Leader does not disclose its sources.” But, I pointed out, the source’s spokesman had already revealed him. McQuaid replied: “As I said, we do not disclose our sources.”

I pressed him about whether the Union Leader had any standards on use of unnamed sources. He did not reply.

This is outrageous on multiple levels. First, the only reason to afford Gingrich anonymity to deliver the self-serving defense of his own conduct would be to, as Hammond revealed, spare him from revealing what he was doing, namely engaging a Romney surrogate. In doing so, the Union Leader made itself an arm of the Gingrich campaign and misled its readers into thinking Gingrich himself was remaining above the fray.

I asked Ari Fleischer, former White House press secretary, for his take. He is neutral in the primary and has known Gingrich for more than 15 years. He responded, “I find the whole thing bizarre. Journalistically, the Union Leader never should allowed it, but more importantly, behaving one way in public and another way in private is a problem for Newt. If he’s going to act above it all, he needs to conduct himself above it all.”

As for McQuaid’s refusal to discuss the matter, his comment on not ”revealing” sources is disingenuous. The source revealed himself. Now, McQuaid is hiding behind a journalistic standard that no longer is applicable.

The Union Leader can endorse whomever it pleases. McQuaid need not even make a reasoned argument for its choice. But to then co-opt its news reporters and enlist them in an effort to boost the man they endorsed is wrong and brings discredit on the paper, its publisher and its reporters. The rest of its coverage of the 2012 presidential primary is now suspect.

It’s a revealing episode and a caution that when a publication with strong leadership goes “all in” for a candidate, no one comes out looking well.