Jay Sekulow, Trump's private attorney, in 2015. (Steve Helber/AP)

Senate Majority Leader Mitch McConnell (R-Ky.) recently declared “case closed” on questions about President Trump and Russia. But we’ve been getting glimpses into congressional investigations that show it’s anything but, and that Congress actually has much to investigate from the Mueller report.

The latest is the revelation that Michael Cohen says another Trump lawyer told him to lie to Congress about then-candidate Trump’s business dealings with Russia. We know that Cohen, Trump’s longtime lawyer now in prison, admitted to lying to Congress in 2017 that Trump’s attempts to build a tower in Moscow had ended before voting began in the Republican primaries. Those efforts actually went all the way through the primaries. On Monday, The Washington Post reported that in private congressional testimony, Cohen said that Trump attorney Jay Sekulow told him to give a false date to Congress. Now House Democrats are trying to get Sekulow and others in Trump world to testify.

Sekulow had previously denied the allegation. But at the very least, we now know it’s possible that Cohen wasn’t acting on his own to protect Trump from appearing conflicted on Russia while running for president, right as Russia was interfering in the election to help Trump win. Was there a team working to protect Trump from that politically inconvenient business deal?

That’s an unanswered question about the president’s potential conflict of interest — and how far he went to protect himself — that is left open-ended after a nearly two-year independent investigation by special counsel Robert S. Mueller III.

Not that Mueller didn’t want to know. Mueller tried to get Trump and his attorneys to talk to him about this, but neither did, The Post reports.

Ultimately, Mueller couldn’t determine the lengths to which Trump tried to keep his Russia business deals secret from voters. And while it’s true that Mueller did not find actions taken by Trump’s campaign that met the legal definition of the crime of conspiracy to work with a foreign power, he did uncover a number of Russia connections he felt worth noting, such as how Trump and his campaign seemed to welcome Russia’s help when offered.

To that end, even a Republican-led investigation appears to still have questions. The Senate Intelligence Committee is still investigating Russian election interference, and it recently issued a subpoena to force Trump’s son Donald Trump Jr. to come back and answer questions from senators, in what senators framed as a follow-up to Trump Jr.'s original interview with the committee last year.

Trump Jr. notably responded “I love it” when told that a Russian had dirt on Hillary Clinton as part of a Russian government effort to help his father win.

So why did the eventual president of the United States have hundreds of millions of dollars on the line with Russia as he was running for president, in an election Russia tried to help him win? And how far did those under him go to cover that up from voters? And how open was his campaign to getting help from Russians?

These are not questions Democrats in Congress have made up to investigate to make the president look bad. These are serious questions that could get at the heart of U.S. election integrity that Mueller was not able to answer, and that naturally fall to Congress to investigate. You could say Congress is doing its job by not closing the case on Trump and Russia.