In the last week, we’ve learned several new things about past and ongoing contacts between President Donald Trump, his aides, and Russia. These revelations cast doubt on the president’s denials of collusion. Trump and his surrogates dismiss these stories, but their answers raise further questions. Those questions can and should be investigated.

Here are the new developments. First: A week ago, documents filed by Paul Manafort’s lawyers revealed that in early 2016, while working on Trump’s campaign, Manafort shared the campaign’s private poll data with Konstantin Kilimnik, an associate connected to Russian intelligence.

Second: On Friday, the New York Times reported that Trump’s firing of then–FBI Director James Comey in May 2017, compounded by the president’s suspicious behavior, led the FBI to open an investigation into whether Trump was “working on behalf of Russia against American interests.”

Third: On Saturday, the Washington Post reported that within the White House, Trump has “gone to extraordinary lengths to conceal details of his conversations with Russian President Vladi­mir Putin, including on at least one occasion taking possession of the notes of his own interpreter and instructing the linguist not to discuss what had transpired with other administration officials.”

Confronted with these disclosures, Trump has responded with lies. On Saturday, he called special counsel Robert Mueller and his team of prosecutors, who have run one of the most opaque investigations in history, “leaking machines.” Trump also suggested that he has been “tougher than any other president” on Russia, a claim that would have elicited laughter from Harry Truman, John F. Kennedy, Ronald Reagan, or the members of Congress who have forced Trump to accept sanctions against Putin. Trump also told Fox News host Jeanine Pirro that federal agents “broke into” the office of his former lawyer, Michael Cohen—a lie that Trump continues to repeat even though it has been debunked.

Some of Trump’s responses, however, invite further investigation. They point to additional information that would clarify what he did with his Russian counterparts and whether he’s telling the truth now. Here are four claims worth pursuing.

1. Trump doesn’t mind disclosing the contents of his meetings with Putin. On Saturday, Pirro quizzed Trump about the Post story. “Why not release the conversation that you had with President Putin in Helsinki?” she asked, noting that Trump could also release documents embarrassing to the FBI officials who had investigated him. Trump replied: “I would. I don’t care. … I’m not keeping anything under wraps. I couldn’t care less.”

If Trump doesn’t care, then he’ll release the information that Congress and his own aides have sought. He could start with the interpreter’s notes from his July 2017 meeting with Putin. Trump’s confiscation of those notes thwarted officials from the State Department and the National Security Council who tried to find out what had transpired in the meeting. Or Trump could authorize the interpreter from his July 2018 meeting with Putin—the one in Helsinki—to testify about what was said, as members of Congress have requested. These steps would show good faith. Rejecting them would show the opposite.

2. Trump treats Putin the same way he treats other world leaders. “I have a one-on-one meeting with Putin like I do with every other leader,” Trump told Pirro. On Pirro’s program and in remarks to reporters on Monday, the president cited three such leaders: President Xi Jinping of China, Prime Minister Shinzo Abe of Japan, and Prime Minister Narendra Modi of India. “I meet with all of them, but nobody says anything,” Trump told Pirro. “But I meet with Putin, and they make a big deal.” Speaking to the press on Monday, White House counselor Kellyanne Conway made the same pitch. Trump’s one-on-one meetings with Putin, she averred, were no different from his meetings with Modi and North Korean dictator Kim Jong-un.

That raises an obvious question, which a reporter posed to Conway: “Did the president destroy notes with other world leaders, or was this exclusive to Putin?” To be more precise, was the withholding of notes and information about such meetings—from other administration officials—“a standard practice? Was this something he did with other world leaders?” Conway told the reporter that she couldn’t answer that question. “I have not been able to discuss this at length with him,” she said.

She’d better ask him. So should Congress. If Trump hasn’t kept similar control of information about meetings with other leaders, that’s a sign of a corrupt relationship.

3. There was nothing unusual about sharing poll data with Kilimnik. Manafort “only gave him polling data. That’s handed out all the time,” Trump’s lawyer, Rudy Giuliani, told the New York Daily News. In an interview with the Hill, Giuliani added: “There is no legal protection of polling data. You can give it to anyone. Campaigns leak polling data all the time.”

The idea that internal polls are “handed out all the time” to business associates in other countries would surprise anyone who has worked in senior positions on campaigns. Internal polls are held close because the questions are strategically useful (they’re designed to inform campaign plans, not to inform the public) and, if leaked, would be just as useful to the other side. But if Trump’s campaign handed out such numbers “all the time,” there must be other countries whose intelligence contacts also received them. Can Trump, Manafort, or Giuliani name any such countries? Or does Russia—and its Ukrainian proxies, for whom Kilimnik also worked—stand, in this respect, curiously alone?

4. Trump was angry about the exposure of his conversation with Russia’s foreign minister. When reporters asked Conway why the president had seized the notes from his July 2017 conversation with Putin, she explained that Trump had been irked by “a great number of leaks,” especially from “an Oval Office meeting in May of 2017. Contents of that leaked. And so there was great concern at the time.”

That’s a remarkable answer. The Oval Office meeting in question was with Sergey Lavrov, Russia’s foreign minister. It took place on May 10, 2017, a day after Trump fired Comey, and it was closed to the press. In the meeting, Trump told Lavrov, “I just fired the head of the FBI.” He added: “I faced great pressure because of Russia. That’s taken off.” Trump also alarmed his aides by sharing sensitive intelligence with Lavrov.

In short, the meeting was deeply incriminating. The only reason we know about its contents is that a document “based on notes taken from inside the Oval Office” was “circulated as the official account of the meeting,” according to the New York Times, which reported Trump’s comments. Conway’s citation of this leak as the grounds for Trump’s subsequent efforts to control information—particularly by blocking the circulation of notes from his conversations with Putin—raises grave questions about what Trump said to others in the White House, and to his Russian contacts, about the exposure of his comments to Lavrov.

These four lines of inquiry aren’t baseless, biased, or idle. They’re directly implicated by statements from Trump and his surrogates, and they can be resolved by information that’s already in the possession of the White House and the Trump campaign. The president hasn’t given the right answers. But he’s exposing all the right questions.