Over to you, Congress.

Special counsel Robert Mueller's first public statement on his investigation into Russian interference in the 2016 presidential election may indeed be his last. Mueller's 10-minute Wednesday appearance, in which he did not take questions, made clear that he believes his report speaks for itself and that he will not voluntarily agree to testify before Congress.

Mueller also believes that Russia poses an ongoing threat to our democracy — a belief convincingly rooted in the dozens of indictments he handed down in connection with his investigation.

Yet those impeachment proponents who hoped Mueller would provide new material for their cause were likely disappointed with his remarks, though some were quick to point to his comment that "if we had confidence that the president clearly did not commit a crime, we would have said so. We did not, however, make a determination as to whether the president did commit a crime."

Indeed, Mueller provided the kind of fact-based executive summary of his work that Americans should have received from Attorney General William Barr, who instead chose to spin the report in President Donald Trump's favor before its release last month. It was Trump-appointee Barr — not Mueller — who concluded the special counsel lacked sufficient evidence that the president obstructed justice. But Mueller and Barr do agree on a critical point: that Trump could not be charged with a crime while in office even if there were evidence to do so.

"The opinion says the Constitution requires a process other than the criminal justice system to formally accuse a sitting president of wrong­doing," Mueller said, referring to a Justice Department legal opinion.

That's where Congress comes back into the picture, and Mueller obviously wants no part of the political circus surrounding a potential impeachment. Neither has House Speaker Nancy Pelosi — at least before Wednesday — fearing impeachment hearings would backfire on Democrats in November 2020. Mueller could be subpoenaed, but he made it clear that any testimony would not go beyond the findings in his report.

For his part, Trump has adopted "No collusion, no obstruction" as a mantra, and White House press secretary Sarah Sanders repeated it in a Wednesday statement released after Mueller spoke. There was no mention of Russian interference in Trump's Twitter stream or from Sanders.

The House Judiciary Committee should proceed with its Trump-Russia investigation even as the president continues to block its subpoenas and other investigative efforts. Americans deserve the fullest possible accounting of this sorry chapter in the nation's history. And Congress must renew its focus on ensuring the country can have full confidence in the U.S. election system going forward.

Even though Mueller reaffirmed a central finding of his investigation — that there was "insufficient evidence to charge a broader conspiracy" by the Trump campaign — he concluded that "there were multiple, systematic efforts to interfere in our election. And that allegation deserves the attention of every American."

That includes Trump, who has dismissed Russia's role in his 2016 victory and seems disinterested in preventing possible future meddling, preferring to carry on his bromance with Vladimir Putin.

Mueller's warning is especially disturbing in light of an April 24 New York Times story reporting that former Homeland Security Secretary Kirstjen Nielsen had been instructed not to bring up the topic of Russian election interference in front of Trump, who does not react well when the legitimacy of his election is questioned.

That's troubling on many levels, but mostly because the integrity of America's election process — not the president's fragile self-esteem — should be of paramount concern now.