National security adviser Michael Flynn sits in the front row before the start of a news conference in the White House on Feb. 10. (Carolyn Kaster/Associated Press)

Michael Flynn’s real problem isn’t the Logan Act, an obscure and probably unenforceable 1799 statute that bars private meddling in foreign policy disputes. It’s whether President Trump’s national security adviser sought to hide from his colleagues and the nation a pre-inauguration discussion with the Russian government about sanctions that the Obama administration was imposing.

“It’s far less significant if he violated the Logan Act and far more significant if he willfully misled this country,” said Rep. Adam B. Schiff (Calif.), the ranking Democrat on the House Intelligence Committee, in a telephone interview late Friday. “Why would he conceal the nature of the call unless he was conscious of wrongdoing?”

Schiff said the FBI and congressional intelligence committees should investigate whether Flynn discussed with Russian Ambassador Sergey Kislyak in late December the imminent imposition of sanctions, and whether he encrypted any of those communications in what might have been an effort to avoid monitoring. Schiff said that if some conversations were recorded by U.S. intelligence agencies, “we should be able to rapidly tell if Gen. Flynn was being truthful” when he told Vice President Pence and other colleagues that sanctions weren’t discussed.

Flynn’s contacts with Kislyak were first disclosed in my Jan. 12 Post column, so I have a window on the events surrounding that disclosure. I reported that, according to a senior U.S. government official, Flynn had phoned Kislyak several times on Dec. 29, the day the Obama administration announced the expulsion of 35 Russian diplomats in retaliation for the Kremlin’s hacking attack during the 2016 presidential campaign.

“What did Flynn say, and did it undercut the U.S. sanctions?” the column asked. We still don’t know the answers to those questions — but new reporting has made them more pertinent than ever. Flynn needs to clarify what happened, or risk losing his credibility with National Security Council colleagues and the public.

White House senior policy adviser Stephen Miller on Feb. 12 declined to say if President Trump still trusts national security adviser Michael Flynn. Meanwhile, Democrats scolded Flynn after The Washington Post reported that Flynn discussed sanctions with Russia's ambassador to the U.S. during the transition of power. (Bastien Inzaurralde/The Washington Post)

The Flynn-Kislyak contacts gained new attention when The Post reported Thursday that the FBI was continuing to examine Flynn’s communications with the Russian official, and that the two men had discussed U.S. sanctions, contrary to the Trump team’s denials.

The possibility that Flynn violated the Logan Act was noted in that January column. But Flynn’s defenders reasonably countered that there were good public-policy reasons for a future national security adviser to talk with the ambassador of a major power about future policies. That’s one reason the Logan Act has never been enforced.

The harder question is whether Flynn was open about his conversations, which Flynn should have known would probably be controversial, especially given his past interaction, including a paid speech, with Russia Today, a Kremlin mouthpiece.

The White House needs to clarify several anomalies. Perhaps these are just the missteps that afflict any new White House team, but they’re puzzling, at best.

Why did the Trump team give slow, initially conflicting and apparently incomplete accounts of the conversation? A Trump campaign spokesman forwarded my request for comment to Flynn’s team on Jan. 12, about seven hours before the column appeared. But there was no response until the next morning, when a colleague of Flynn’s said the retired lieutenant general had talked with Kislyak sometime between Dec. 27 and Dec. 29.

About an hour later, Trump press secretary Sean Spicer confirmed the Flynn-Kislyak contacts in a public briefing, but said they had come in texts on Dec. 25 and in a phone conversation Dec. 28, when it was widely reported sanctions were imminent. Sources continued to tell the Associated Press that day that there had been a call on Dec. 29.

The crucial question is what Flynn and Kislyak discussed. The Flynn associate told me initially that the two explored timing of a future conversation between Trump and Russian President Vladimir Putin. A Trump campaign spokesman told me several hours later that Kislyak had also told Flynn that a Trump representative should attend a peace conference on Syria that would take place after the inauguration in Astana, Kazakhstan.

Various Trump team members said Flynn hadn’t talked to Kislyak about the sanctions that were being announced near-simultaneously with the communications, whichever date you choose. That’s apparently what Flynn told Pence, too. But this denial became inoperative Thursday, when a spokesman said Flynn “indicated that while he had no recollection of discussing sanctions, he couldn’t be certain that the topic never came up.”

A national security adviser’s success depends on maintaining trust, especially with his White House colleagues. After Flynn’s changing statements about a sensitive issue, he has a trust deficit that can only be filled with a full accounting of what happened — one that is consistent with any record that was compiled by U.S. intelligence agencies of his calls with Kislyak.