It was evident from the outset that House and Senate Democratic watchdogs weren't going to accept Trump Attorney General Bill Barr's terse, ambiguous summary of the Mueller report's claims as the end of investigative efforts into Trump campaign actions during 2016.

House Judiciary Committee Chairman Jerrold Nadler almost immediately announced that he would be calling Barr before his committee to explain, in light of "the very concerning discrepancies and final decision making at the Justice Department following the Special Counsel report", why he went beyond Mueller's report to make the decision that Trump would not be criminally charged—a decision that appeared to watchers of Mueller's work to rest on a tortuously narrow interpretation of the known evidence.

Speaker of the House Nancy Pelosi and Senate Minority Leader Chuck Schumer were more pointed still in a joint statement responding to Barr's letter.

Attorney General Barr’s letter raises as many questions as it answers. The fact that Special Counsel Mueller’s report does not exonerate the president on a charge as serious as obstruction of justice demonstrates how urgent it is that the full report and underlying documentation be made public without any further delay. Given Mr. Barr’s public record of bias against the Special Counsel’s inquiry, he is not a neutral observer and is not in a position to make objective determinations about the report. And most obviously, for the president to say he is completely exonerated directly contradicts the words of Mr. Mueller and is not to be taken with any degree of credibility. “Congress requires the full report and the underlying documents so that the Committees can proceed with their independent work, including oversight and legislating to address any issues the Mueller report may raise. The American people have a right to know.

Barr's summary is an indication that the Justice Department itself will not be indicting Trump based on their interpretation of the presented evidence—an expected outcome, based on Barr's own public hostility towards that outcome prior to his appointment. But the same summary mentions only in glancing reference that evidence was found suggesting Trump acted to obstruct justice; Barr did not dispute that the evidence existed, but came to a conclusion that it was not sufficient to lodge criminal charges against the sitting president.

That's not the same as saying the evidence in the report is not sufficient to warrant congressional deliberation, and possibly an impeachment investigation, against Trump. Barr is only making the determination that he himself won't be touching it.

And that's not going to fly with Democrats. They're going to insist that lawmakers from both parties see that evidence, and make those determinations, themselves.