The U.S. Justice Department appointment of former FBI Director Robert Mueller to lead a criminal investigation into possible collusion between President Trump’s campaign and the Russia government is a welcome and overdue move to bring integrity and seriousness of purpose to the daily revelations that threaten to overwhelm Washington.

But more is needed. An old-school, by-the-book prosecutor, Mueller is expected to undertake a meticulously thorough examination and has the sweeping powers necessary to do so. He will be focused on whether the president, his campaign associates or members of his administration have or had illegal ties to an adversarial nation. If laws were broken, he will determine which ones and to what extent. Mueller also remains bound by Justice Department rules and supervision. His decisions, actions and budget can be reined in at any time. And a criminal probe, no matter how thorough, will not address the larger issues that confront this nation about how to ensure that U.S. elections and governments are protected against foreign interference.

An independent, 9/11-style commission could examine the broader threat to American democracy posed by what intelligence agencies all agree was Russian meddling in the 2016 election. This nation must learn the extent of those actions and what must be done to protect the U.S. against attempts to subvert elections and institutions.

Republicans should be leading those efforts, not blocking them. Despite control of the executive and legislative branches, their agenda is getting bogged down in an ceaseless stream of self-generated crises by an administration that appears to be going off the rails. To salvage their own prospects, let alone those of the country at large, Republicans should want to halt the downward spiral of this administration.

And while the special counsel is needed, the criminal investigation cannot become an excuse for not addressing those larger issues. Congress, despite four active investigations, may not be up to the job. Its work has been painfully slow and problem-plagued. House Intelligence Committee Chairman Devin Nunes recused himself from the Russian investigation after he ran to the White House with sensitive information, and yet a new report shows he remains involved. House Oversight Chairman Jason Chaffetz may be resigning his seat next month, reportedly lured by the prospect of a berth at Fox News. Sen. Lindsay Graham is already saying of his Judiciary Committee investigation that Mueller’s appointment “probably well shuts it down.”

An outside commission not answerable to the administration would have none of these issues. Given the impending 2018 midterm elections, Congress cannot wait until Mueller has wrapped up his work. Confidence must be restored that American elections and institutions are well-insulated against interference by malicious foreign governments.

One courageous Republican, Rep. Justin Amash of Michigan, has signed on to a bill by California Democratic Rep. Eric Swalwell to form such a commission. But efforts to establish an independent body have been blocked by House Speaker Paul Ryan, whose deference to Trump ill-serves his branch’s responsibility to provide a check on executive power.

Democrats are resorting to a maneuver known as a discharge petition, which would allow them to bypass Ryan and bring a bill straight to the floor. As of Friday, they had 191 of 218 signatures needed, including all of Minnesota’s House Democrats but no Republicans.

Rep. Erik Paulsen, R-Minn., recently told an editorial writer that “I am open to any process that would have an independent component,” adding that “I’m absolutely open” to the idea of an independent commission. That’s good, but now he and Minnesota GOP Reps. Tom Emmer and Jason Lewis should join Amash in supporting the bill and signing the petition that could bring it to the House floor.