Obstruction is different—especially when a defendant might have acted with mixed motives. If, say, the president fired FBI Director James Comey because he believed he was a bad manager, but with some thought to the collateral benefit of harming the Russia investigation, that mixed purpose on his part would make it very hard to prove, beyond a reasonable doubt, that he had the requisite criminal intent. He could respond that his real motive was good governance, and it would be a challenge to convince the jury that this wasn’t at least partially true.

BuzzFeed News’s story about Cohen changes the equation. When someone attempts to suborn perjury—which is what lawyers call it when you ask a friend to lie on your behalf—there cannot be any reasonable scenario in which mixed motives might apply. There’s only one reason you ask a person to lie—to conceal guilt—and that, by itself, proves a corrupt motive.

Even the president’s attorney-general nominee, William Barr, would agree with that statement. As he wrote in a memorandum long before these allegations came to light: “If a President knowingly … suborns perjury, or induces a witness to change testimony, or commits any act deliberately impairing the integrity or availability of evidence, then he, like anyone else, commits the crime of obstruction.”

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So the Cohen allegations, if true, are a legal game changer. And yet perhaps the story will not make that much of a difference in the legal world, because as I’ve written before, Justice Department policy prohibits the special counsel from indicting a sitting president, and Robert Mueller is exceedingly unlikely to violate that policy.

Thus, the real question is whether the Cohen blockbuster also has political salience—might it change the equation in the House and Senate regarding impeachment? It seems as though it should. Remember that in 1998–99, during the investigation of President Bill Clinton, the most significant charges against him involved very similar allegations about suborning perjury.

Specifically, in the articles of impeachment adopted by the House of Representatives, Clinton was accused of obstruction for having attempted to persuade Monica Lewinsky and Betty Currie to lie about his conduct. He was charged with asking Lewinsky to lie in the civil suit brought by Paula Jones, and with coaching Currie to give false testimony in the criminal grand-jury investigation being conducted by the independent counsel. Fourteen currently serving Republican senators were in Congress back then, and all thought that obstruction of justice was an impeachable and removable offense—voting for either impeachment in the House or conviction on the obstruction charge in the Senate.

Indeed, as then-Representative, now-Senator Lindsey Graham put it: “If you believe he obstructed justice in a civil rights lawsuit, don’t move the bar any more … You don’t even have to be convicted of a crime to lose your job in this constitutional republic if this body determines that your conduct as a public official is clearly out of bounds in your role … Impeachment is not about punishment. Impeachment is about cleansing the office. Impeachment is about restoring honor and integrity to the office.”

Those senators must feel deeply politically uncomfortable right now. Many of them (most notably Graham) built their careers on the proposition that Clinton had obstructed justice and was unfit for office; today, they are faced with the possibility that Trump might have done nearly the same thing. How will they react now?

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