Washington • What has Trey Gowdy been smoking?

And can we order it in bulk?

The South Carolina Republican, who roared into Congress in the tea-party election of 2010, has been one of the most partisan, vitriolic and conspiracy-minded legislators in his eight years here. As recently as January, he was demanding answers about a bogus “secret society” within the FBI and special counsel Robert Mueller’s probe.

But since then, Gowdy has contracted a case of late-onset honesty.

On “CBS This Morning” on Wednesday, Gowdy, chairman of the House Oversight Committee, dismissed the notion, propagated by President Trump, that the FBI had a “spy” in the Trump campaign. He said the FBI did what it “should have done” and that informants such as the one used by the FBI are used “all day, every day by law enforcement.”

Gowdy told Fox News on Tuesday that, after a classified briefing on the subject, “I am even more convinced that the FBI did exactly what my fellow citizens would want them to do.”

Earlier, Gowdy took issue with his fellow Republicans’ claims that Russia didn’t try to help Trump win the election, saying it was “clear based on the evidence” that Russia sought to defeat Hillary Clinton. And he didn’t join other Republicans in their categorical claim that there was no Trump campaign collusion with Russia.

He also defended the broad mandate of the Mueller investigation, and he delivered a blunt message to Trump to talk to Mueller and give him time and independence: If Trump is innocent, then “act like it.”

Actually, we know exactly what Gowdy is smoking: the sweet herb of retirement. He announced at the end of January that he was leaving Congress, which freed him to speak his mind without fear of a political price. Several of the 48 departing House Republicans have, like Gowdy, become last-minute truth tellers about Trump on their way out, including Thomas J. Rooney, Charlie Dent, Ryan Costello and Ileana Ros-Lehtinen.

A scant few Republicans in Congress deserve praise for speaking out against Trump even before announcing retirement. But most, including Gowdy, deserve the proverbial two cheers for their belated honesty. When all this comes crashing down, they can say they spoke out. But when they could have made a difference, before Trump took a box cutter to the fabric of democracy, they were silent.

Even now, Gowdy is far from a Trump critic. In the same CBS interview, Gowdy defended Trump’s frustration with Attorney General Jeff Sessions’ recusal in the Russia probe. Trump tweeted Gowdy’s defense, ignoring Gowdy’s dismissal of Trump’s nonsense “spy” claim.

And Gowdy always had some law-and-order tendencies that occasionally broke with party orthodoxy. The conspiracy crowd denounced him when the Benghazi committee, which he led, failed to validate their dark theories about Clinton.

But he was, in his eight years, one of the great GOP flamethrowers. He referred to his lengthy Benghazi probe as a “trial” of Clinton, and after a promising initial hearing, it quickly devolved into a partisan fight that singled out bugbears of the right such as Clinton aides Sidney Blumenthal and Huma Abedin.

His theatrical outbursts at committee hearings — “I want indictments!” he bellowed during one hearing into overspending — grabbed headlines. He spearheaded the effort to hold Internal Revenue Service official Lois Lerner in contempt of Congress, and he claimed that the Obama administration’s refusal to cooperate with Congress was “proof” that President Barack Obama knew about the botched gun-running program “Fast and Furious.”

Gowdy, though undertaking three investigations into the Trump administration, has been rather more forgiving of this administration’s refusal to cooperate. Democrats on his committee say he hasn’t issued a single subpoena to the administration. When I asked Wednesday about Gowdy, Elijah E. Cummings (Md.), the top Democrat on the committee, was grudging: “We now live in a kind of alternate universe when individual Republicans get massive praise just for acknowledging the obvious and restating basic facts.”

Gowdy’s spokeswoman, Amanda Gonzalez, said he wouldn’t speak with me for this column — not a complete surprise given that I had previously identified him as “Rep. Trey Gowdy (R-Benghazi).”

In a recent CNN interview, Gowdy complained about the partisan atmosphere, saying “it really is just about winning” and criticizing Republicans whose objective was “not to do good for the country.” To Politico, he lamented that “there is more civility in a death penalty case than there is in some congressional hearings.”

But Gowdy added to the incivility. Now he’s leaving Washington, like Cincinnatus returning to his fields — or in Gowdy’s case, to the courtroom — and the place is in (even) worse shape than when he arrived.

Better late than never, he’s speaking up on his way out. If only incumbent Republicans were courageous enough to do the same.

Dana Milbank | The Washington Post

Follow Dana Milbank on Twitter: @Milbank.