It was that rare event in Washington, an actual resignation based on principle.

31 years ago this month, William Weld was assistant attorney general in charge of the Justice Department's Criminal Division.

But then, in a move that shocked the capital, Weld, along with five Justice Department colleagues, including the Deputy Attorney General, quit in protest.

The then attorney general, Edwin Mies, was embroiled in controversy under investigation by a special prosecutor over allegations of corruption.

Weld and his colleagues were convinced the swirl of allegations around Mies were tarnishing the reputation of the department.

These are truly resignations of conscience. They simply couldn't work for Ed Mies any longer, one department official told The New York Times.

Weld's resignation was only one of a series of pivotal events in a lengthy career that has included serving on the staff of the House impeachment committee that investigated Richard Nixon, serving as US Attorney in Boston, where he prosecuted mobsters and big financial institutions, and being elected twice in the 1990s as Governor of Massachusetts.

He got some brief attention three years ago when he bolted the Republican Party to run for Vice President on the Libertarian Party ticket.

But now we could get a lot more attention. He's recently announced he set up an exploratory committee to test the waters for a primary challenge to Donald Trump.

We recently said his quote, simply too unstable to carry out the duties of the highest executive office.

How serious as well does he have a chance and how is a one-time top prosecutor does he assess the president's legal troubles?

We'll talk to him about that and lots more on this episode of Skull Buggery.

Because people have got to know whether or not they're presidents of crook, well I'm not a crook.

I told the American people I did not trade arms for hostage. My heart and my best intentions still tell me that's true.

But the facts and the evidence tell me it is not. I did not have sexual relations with that woman.

There will be no lies. We will honor the American people with the truth and nothing else.

I'm Michael Isgov, Chief Investigative Correspondent for Yahoo News.

And I'm Dan Clyde, Minister of Yahoo News.

You know, it is so interesting to look back at that moment at the end of the Reagan administration when people at the Justice Department actually quit on an issue of conscience and principle.

Yeah, I started covering justice just a few years after that.

And I remember that that event hung over the department. It was this dramatic thing.

And what it said was that if you politicize the Justice Department or if you acted as Attorney General in a way that without integrity, there were consequences for that.

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