The contradictions of former FBI director James Comey keep piling up. The latest came Friday when Senate Judiciary Chairman Chuck Grassley provided new evidence that Mr. Comey told Congress a different story last year about the truthfulness of former White House national security adviser Michael Flynn than Mr. Comey is now telling the public.

In a letter to the FBI and the Justice Department seeking documents, Mr. Grassley relates that Mr. Comey “touched on” the Flynn case before the Judiciary Committee on March 15, 2017. A “career, non-partisan law enforcement officer” was present and took notes. “According to that agent’s contemporaneous notes,” Mr. Grassley writes, “Director Comey specifically told us during that briefing that the FBI agents who interviewed Lt. General Michael Flynn, ‘saw nothing that led them to believe [he was] lying.’”

Mr. Grassley says this contradicts Mr. Comey’s “public statements during his current book tour denying any memory of those comments,” and that Mr. Comey “led us to believe during that briefing” that “the Justice Department was unlikely to prosecute [Mr. Flynn] for false statements made in that interview.”

The House Intelligence Committee has released a transcript of Mr. Comey saying the same thing about Mr. Flynn, so this is the second time Mr. Comey has been contradicted on the point. In December Mr. Flynn pleaded guilty to making false statements to the FBI, and the question is whether special counsel Robert Mueller pressured him to plead to a crime he didn’t commit. Attorney John Dowd asks the same question in a nearby letter and says Congress should seek the 302 forms filed by FBI agents who did the interviewing.

This is presumably among the documents Mr. Grassley is seeking from Justice and the FBI, which have no good reason to resist cooperating now that Mr. Flynn has pleaded guilty. This would help Americans learn whether Mr. Flynn was telling the truth—and whether Mr. Comey is lying now.