Bill Clinton's blunder: Will he keep messing things up for his wife?

Democratic presidential candidate Hillary Clinton reacts as former President Bill Clinton smiles at her New Hampshire presidential primary campaign rally, Tuesday, Feb. 9, 2016, in Hooksett, N.H. (AP Photo/Elise Amendola)

Has Bill Clinton become a liability for his wife?

This is not the first time we’ve had to ask that question. The former president caused Hillary all kinds of headaches in 2008, getting into it with Barack Obama, making comments viewed as racially insensitive, and overshadowing her with his formidable presence. And his history of sexual misconduct, then and now, served as an unfortunate backdrop for a candidate running as a champion of women’s rights.

He has seemed on better behavior this year, a low-key presence on the trail, sometimes looking frail and clearly having lost a step or two, but avoiding any major blunders.

Until now.

Clinton’s private-plane meeting with Loretta Lynch while his wife is under investigation was such a colossal mistake that even days later it is still hard to believe.

As an old Justice Department reporter, I can tell you that the Lynch-Clinton meeting is a head-slapping case of bad judgment. It’s not just about “bad optics.” Law enforcement officials aren’t supposed to engage in ex parte communications with people who could be part of a criminal case, and Bill Clinton is a potential witness. He lives with the woman who kept a private emails server at their home. The Clinton Foundation, which he launched, could be part of the probe.

The ex-president is a lawyer who served as attorney general of Arkansas. What’s more, he went through the Ken Starr investigation, back in the days when we had special prosecutors, that essentially led to his impeachment. He knows about prosecutors and witnesses and criminal probes.

I presume that they were in fact chatting about grandchildren and golf, because I don’t think either is dumb enough to discuss a pending criminal matter. But that makes it all the more stunning that both would risk the appearance of impropriety over such a trivial conversation.

Much of the press was slow to pick up on the importance of this meeting. The story didn’t fully explode until the Justice Department leaked word that Lynch would accept the recommendation of the FBI and career prosecutors in the case.

Lynch’s acknowledgement to the Washington Post’s Jonathan Capehart that this has “cast a shadow” over the case shows that she cannot defend the indefensible. Clinton may be a charming guy, but she should have kicked him off that plane.

Lynch is now saying she always planned to follow whatever the prosecutors concluded. That is the overwhelmingly frequent practice. For Lynch to overrule her staff on a proposed indictment of Hillary Clinton would cause a massive political firestorm.

So a lot of this is about maintaining public confidence in a treacherous situation in which President Obama’s top cop is investigating the former Cabinet member he’s endorsed as his successor.

As for Bill, he’s not just any spouse. He would be the first president to return to living in the White House, albeit in a different role. Hillary has said he will play a major role in helping her boost the economy, and obviously he would function as her top political adviser.

This is the flip side of the old argument that Bill Clinton made in 1992, that voters will get two for the price of one.

In light of what happened last week, that may not be a bargain everyone wants to make.