It’s bad enough that President Donald Trump is flirting with obstruction of justice by suggesting that he’s thinking of pardoning Paul Manafort as a reward for Manafort’s refusal so far to cooperate with the special counsel. But Rudy Giuliani, a former U.S. attorney, is part of the effort — and his latest comments are so close to the line of obstruction that they actually may have crossed it.

Giuliani, now one of Trump’s personal lawyers, told The Washington Post on Thursday that Trump had asked him about pardoning Manafort, who had been Trump’s presidential campaign manager. According to Giuliani — speaking to the newspaper, and thus to Manafort — Giuliani told Trump to wait until the investigation by special counsel Robert Mueller was completed.

This sounds like a direct message to Manafort: Wait out Mueller, and Trump will pardon you. Giuliani's message goes beyond what Trump has said thus far because it adds the component of specific timing to Trump's generalities.

Timing is all-important to Manafort, who must be asking himself constantly whether Trump is bluffing. If Manafort, who was convicted this week on eight counts of tax fraud, wants to trade information with Mueller's team in exchange for a recommendation of a shorter prison term, he does not have much time. Once he is sentenced, his chance is gone, and he has to rely on a pardon to reduce his sentence. So Giuliani's comments are highly material to the question of whether Manafort is being offered an inducement not to cooperate with officials.

Of course, it's hard to prove definitively that Giuliani or Trump is making a direct offer to Manafort. But follow this thought experiment:

Suppose Giuliani had said, “If Paul Manafort is listening, he should know that Donald Trump won’t pardon him until after the Mueller investigation is over. Then, he will — provided Manafort keeps his mouth shut.”

That statement would certainly qualify as obstruction of justice. It could be prosecuted as a crime, even without further evidence. Giuliani would be corruptly inducing Manafort not to cooperate with an ongoing criminal investigation in exchange for the promise of a pardon.

And Giuliani, unlike Trump, cannot try to claim that the pardon power itself gives him the right to make the offer. He's not the president.

Now ask yourself: How could Giuliani get any closer to making the imaginary statement without actually saying the words? Manafort has been convicted and is awaiting sentencing. He’s listening to anything Trump might be communicating to him. All that’s missing is the form of words directly offering the quid pro quo. But that offer is implicit — and understood by everyone.

If you want further proof of Giuliani’s intent, consider the genuinely outrageous fact that Trump asked the opinion of his own criminal lawyer about when to pardon Manafort. That fact alone should be a scandal — or would be if we weren’t living in such a topsy-turvy world.

The president is not supposed to be asking his personal attorney about how to exercise a presidential power that he is not supposed to use to protect himself. The White House counsel is the right person to ask for a question about pardon. He works for the president in his official capacity.

Giuliani only works for Trump in so far as his job is to get Trump to avoid criminal liability. The fact that Trump is discussing the Manafort pardon with him is strong evidence that Trump is thinking of the pardon as a tool for protecting himself. That's corrupt intent. That's obstruction of justice.

The fact that Giuliani is the vehicle of this crime-in-plain-sight is especially shameful. Hard as it may be to remember, he was once a decorated law enforcement official.

He must know exactly how illegitimate it is for him to be involved in dangling a pardon in front of Manafort. He must know that it is wrong, legally and ethically.

I understand that in the universe where Trump's former personal lawyer, Michael Cohen, has implicated the president in a federal crime under oath in open court, Giuliani's actions may seem like just another shenanigan of a Trump hanger-on. But as a nation committed to preserving the rule of law, we can't afford to define deviancy down quite that far. Lawyers are still lawyers. The law is still the law, even if the president seems to be in the habit of flouting it.

One concrete step would be for the New York State Bar to investigate Giuliani on ethics grounds for his statements about Manafort. Proving corrupt intent would not be necessary for a sanction by the bar.

A stronger step still would be for the U.S. Attorney’s Office for the Southern District of New York, Giuliani’s old office, to open an investigation of its former boss for conspiracy to obstruct justice. The proof of corrupt intent would have to be circumstantial. But it could potentially be satisfied by Giuliani’s words — and by the facts that he himself has narrated about Trump asking his criminal attorney for advise on the exercise of the pardon power in the case of someone who Trump himself has said might be tempted to testify against him.

In Ernest Hemingway's "The Sun Also Rises," one character asks another how he went bankrupt. "Two ways," runs the answer. "Gradually and then suddenly."

What's true of financial bankruptcy is also true of the bankruptcy of the rule of law. It's a slow drip, until it's a flood. Now is the time to address the drip.

Noah Feldman is a Bloomberg Opinion columnist. He is a professor of law at Harvard University and was a clerk to U.S. Supreme Court Justice David Souter. His books include “The Three Lives of James Madison: Genius, Partisan, President.”