It looks like the emerging strategy of the special prosecutor heading the Russia probe could well be to indict President Trump while he’s in office, rather than refer him to the House for impeachment. The prosecutor, Robert Mueller, hasn’t said anything like that. With the pattern of news stories about Mr. Mueller’s investigation and the president’s own statements, though, it doesn’t take a Sherlock Holmes to speculate that the game, unconstitutional though it may be, is afoot.

The latest news is that Mr. Mueller’s investigators are hoping to “turn” — to use Reuters’s phrase — Mr. Trump’s former campaign chairman, Paul Manafort, into cooperating with them in their probe into collusion between the campaign and Russia. Reuters attributes that to “two sources with direct knowledge of the investigation.” The wire quotes officials as saying Mr. Mueller’s team is examining Mr. Manafort’s financial and real estate records.

Reuters suggests that the focus is on Mr. Manafort’s purchase between 2006 and 2013 of “three New York properties, including one in Trump Tower.” The wire reports he “paid for them in full and later took out mortgages against them.” It quotes a “former senior U.S. law enforcement official” as saying that the “tactic is often used as a means to hide the origin of funds gained illegally.” The wire says it “has no independent evidence that Manafort did this.”

The wire also says its sources “did not say whether [Mr.] Mueller has uncovered any evidence to charge Manafort with money laundering.” It does quote one of its sources as saying: “If [Mr.] Mueller’s team can threaten criminal charges against Manafort, they could use that as leverage to convince him to cooperate.” Mr. Manafort’s spokesman is quoted by Reuters as saying: “Paul Manafort is not a cooperating witness. Once again there is no truth to the disinformation put forth by anonymous sources and leakers.”

The news desk at the Times was apparently asleep when this story moved (Drudge was all over it). Then again, too, the Times does have a terrific scoop, by one of its aces, Charlie Savage, on the question of whether a sitting president can be indicted. It’s about a memo commissioned by the special prosecutor who pursued President Clinton, Judge Starr. The memo, obtained by the Times through a freedom of information request, reckons a sitting president can be indicted.

It’s not hard to find others who disagree with that conclusion. Which may be why Judge Starr — like Leon Jaworski, who pursued President Nixon — flinched from seeking indictments and instead sent the matter over to the unambiguously constitutional authority, the House Judiciary Committee, which ended up drafting articles of impeachment against both presidents. Mr. Mueller may not like that route, if the House is controlled by the Republicans.

Meantime, if Reuters is right, Mr. Mueller will try to turn Mr. Manafort. Far be it from us to suggest — we do not — that Mr. Manafort or anyone else refuse to cooperate with a federal investigation, even one as manifestly political as this. We couldn’t help thinking, though, of Susan McDougal, one of William Clinton’s partners in Whitewater. Convicted of fraud in Whitewater, she did most of her time in the big house refusing to testify against Mr. Clinton.

Could a president pardon someone who might testify against him? This comes up in another Times story, also by Mr. Savage) on the pardon power and how it might be used by a president. It acknowledges that the power is very broad and can be used preemptively, before someone is charged, tried, or indicted. But some of Mr. Savages sources suggest self-interest could cloud that power. It didn’t stop President Clinton, who in the last hours of his presidency granted a full pardon to Ms. McDougal.