A strange thing is uniting Democrats and Republicans in Washington: the widespread disapproval of a meeting between Attorney General Loretta Lynch and former President Bill Clinton on an airport tarmac in Arizona.

Lynch told reporters the impromptu conversation on her government aircraft in Phoenix on Monday centered on social issues, from talk of grandchildren and Clinton's golf game to their recent travels. Nothing came up, the attorney general said, about any ongoing Justice Department investigations.

But the chat took place in the midst of an FBI investigation into the security of Hillary Clinton's private email server, which she used to conduct government business as secretary of state. And that's creating a major appearance problem for the presumptive Democratic nominee for the White House and the top federal prosecutor in the country.

Democratic political strategist David Axelrod tweeted:

On CNN, Sen. Chris Coons, D-Del., praised the attorney general for her law enforcement bona fides but offered this advice: "I think she should have said, 'look, I recognize you have a long record of leadership on fighting crime but this is not the time for us to have that conversation. After the election is over, I welcome your advise and input.'"

Clinton's political opponent in the race for the White House was less measured. Republican Donald Trump told radio talk show host Mike Gallagher the meeting was "terrible."

"I think it's the biggest story, one of the big stories of this week of this month, of this year," Trump declared. "I've been talking about the rigged system, how it's rigged and, you know, this is terrible ... You see a thing like this and even in terms of judgment, how bad of judgment is it for him or for her to do this? I mean, who would do this? "

The number two Republican in the U.S. Senate, John Cornyn, had been calling for a special prosecutor to investigate the Clinton email set-up since last September. In congressional hearings since then, Cornyn has pushed the attorney general about the independence of the inquiry and whether the White House was receiving updates on the status of the case.

Cornyn said the disclosure of the meeting between Bill Clinton and Lynch only heightened his concerns. "'This incident does nothing to instill confidence in the American people that her department can fully and fairly conduct this investigation, and that's why a special counsel is needed now more than ever," Cornyn said in a statement.

From the standpoint of legal ethics, Lynch did nothing wrong, said New York University law school professor Stephen Gillers. Gillers said he didn't think the attorney general needed to recuse herself from overseeing the email probe. But Gillers took a sterner tone with Bill Clinton.

"It was the height of insensitivity for the former president to approach the attorney general," Gillers said. "He put her in a very difficult position. She wasn't really free to say she wouldn't talk to a former president," after Clinton boarded her plane in Arizona.

"He jeopardized her independence and did create an appearance of impropriety going on to her plane," Gillers added.

Gillers said he takes Lynch at her word that no sensitive law enforcement matters came up in the 30-minute airport chat.

But, he said, the episode "feeds the dominant narrative that the Clintons don't follow the usual rules, that they're free to have back channel communications like this one and that's true even if we assume as I do that nothing improper was said. The public will be suspicious."

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