Michael Cohen’s guilty plea on Thursday is the strongest evidence yet that House Republicans’ probe into possible Trump-Russia collusion was nothing more than a partisan sham.

Cohen, Trump’s former lawyer and fixer, admitted he lied to Congress about President Donald Trump’s efforts to develop a Trump Tower in Moscow while campaigning deep into 2016. It calls into question just how much Republican investigators on the House Intelligence Committee really cared about corroborating what they were told by people in Trump’s inner circle.

In March, Rep. Mike Conaway (R-TX) — who led the House GOP effort — told reporters “we’ve found no evidence of collusion,” adding that there was “perhaps some bad judgment, inappropriate meetings, inappropriate judgment at taking meetings,” but nothing that amounted to a coordinated and deliberate effort to work with Russians to win the White House.

We now know the panel reached a conclusion without knowing all the facts. Cohen didn’t offer any evidence for collusion, but his newest revelation underscores how little the GOP-led panel aimed to learn the true extent of Trump-Russia ties.

“The committee was likely lied to about the Moscow project,” Andy Wright, a former White House lawyer, told me. The committee’s Republican leadership “refused to test the veracity of Trump aides’ and family members’ testimony by blocking any efforts to compel the relevant documents and communications records,” he added.

Indeed, Republicans mainly issued subpoenas against the Department of Justice and government officials they suspected of conspiring against Trump. They did little to see if there was any conspiracy on the part of Trump or people connected to him.

Democrats on the House Intelligence Committee continue to note that their Republican counterparts never interviewed key witnesses including former National Security Adviser Michael Flynn, former Trump campaign chair Paul Manafort, and Manafort’s associate Rick Gates — all of whom have now pleaded guilty in special counsel Robert Mueller’s investigation.

Still, committee Republicans feel their job is complete. Asked by CNN if they shut down the probe too early, panel member Rep. Mike Turner of Ohio said “absolutely not.”

“We had gotten to the point where either we would be interfering in the Mueller investigation,” he continued, “or we were getting redundant information. I think the special counsel is where this investigation should be.”

Vox reached out to Conaway’s office for comment on why he ended the probe, but they didn’t immediately return our request.

Incoming Democrats will be much tougher on Trump

Democrats remain apoplectic over how Republicans handled the probe. But they will now be in a position restart the investigation when they become the majority party in the House in January.

Rep. Adam Schiff (D-CA), who is widely expected to lead the House Intelligence Committee in the next Congress, told me the way Republicans bought what Cohen first told them is “absurd” and vowed to gather more information from others in Trump’s orbit.

“There are several witnesses we have concerns about,” Schiff said. He specifically mentioned Roger Stone, the notorious political trickster whose ties to WikiLeaks and possible involvement in the release of emails damaging to Hillary Clinton during the presidential campaign is currently a focus of Mueller’s investigation.

It’s unclear if Democrats will find anything else that Republicans didn’t, and surely Mueller can obtain more information than the House committee can ever find. But the point is that the probe should still be open — not closed prematurely to protect Trump.

Committee Republicans “short-circuited the Russia investigation in order to shield the president,” Wright told me.