Sen Angus King expressed concern Sunday that special counsel Robert Mueller’s investigation into possible collusion between Russia and the Trump campaign to influence the 2016 presidential election failed to reach a conclusion on whether President Trump tried to obstruct justice.

King, a member of the Senate Intelligence Committee, and the other members of Maine’s congressional delegation urged – to one extent or another – Attorney General William P. Barr to make Mueller’s report available to the public. They weighed in on Barr’s initial review of Mueller’s investigation – a four-page letter that was delivered on Sunday to congressional leaders from both parties.

In a statement Sunday evening, King said it concerned him that Mueller left the decision on whether Trump obstructed justice to Barr, whom the president appointed as attorney general.

Barr told congressional leaders that Mueller did not find evidence that the Trump campaign or anyone associated with his campaign “conspired or coordinated” with the Russians in their efforts to influence the presidential election despite multiple offers from “Russian affiliated individuals.”

As to whether the president attempted to obstruct justice, Barr told Congress that Mueller did not draw a conclusion one way or the other on the president’s conduct. The special counsel stated that “while this report does not conclude that the President committed a crime, it also does not exonerate him,” Barr wrote.

Barr said he and Deputy Attorney General Rod Rosenstein concluded that the evidence in Mueller’s report was not sufficient to establish that Trump obstructed justice.

King commended Mueller for conducting a “serious, careful and thorough investigation into the events surrounding foreign interference in the 2016 election.”

“At the same time, AG Barr’s topline summary of the Mueller report leaves me with several lingering questions, none more important than his thought process and reasoning surrounding the Special Counsel’s office decision to not make a traditional prosecutorial judgement on the issue of obstruction of justice,” the senator said.

“The Special Counsel chose to provide evidence on both sides of the obstruction question, and allow the AG to interpret difficult legal issues to resolve the matter,” King said. “This resulted in the final determination being made by the Justice Department without providing a fuller outline of its reasoning, a fact that I expect will leave a large segment of the American people with deep concerns.”

Sen. Susan Collin, R-Maine, also a member of the Senate Intelligence Committee, issued a statement late Sunday night on Barr’s announcement on the Mueller probe.

“It is good news for America, regardless of anyone’s political inclinations, that Special Counsel Robert Mueller’s investigation did not find that the Trump campaign had conspired or coordinated with the Russian government to interfere with the 2016 election,” she said

Collins commended Mueller, whose legal team interviewed 500 witnesses, for being thorough, and the Department of Justice for not interfering in the investigation. Now, she said, Barr must release as much of the report as possible, provided he protects national security sources.

“I appreciate Attorney General Barr’s diligence in providing a summary of the Special Counsel’s conclusions so quickly,” Collins said. “It is imperative that the report be released in as complete a form as possible so that the public can fully understand the rationale for the exoneration on the allegations involving coordination or conspiracy with the Russians as well as the inability of Mr. Mueller to reach a conclusion on obstruction of justice.”

U.S. Rep. Chellie Pingree, D-1st District, argued on Sunday for the release of Mueller’s full report.

“Over the course of 22 months, Special Counsel Mueller’s investigation resulted in charges against 37 defendants, seven guilty pleas and the conviction of a Trump campaign associate,” she said in a statement late Sunday afternoon. “The American public needs more than a four-page summary from the President’s hand-picked Attorney General to determine the scope of the Mueller investigation’s findings.”

Pingree said Barr’s letter raises “serious concerns because his summary explicitly does not exonerate President Trump.”

“Congress already voted 420-0 to release the full report and we should expect nothing less than total transparency,” added Pingree

King called on Barr to show Congress and the American people his work and explain his decision while releasing as much of the report as possible without compromising ongoing investigations or divulging classified sources. King said that will be the only way to “protect Americans’ full faith and confidence in our system of government.”

U.S. Rep. Jared Golden, D-2nd District, said Sunday evening that Barr should make the special counsel’s report available to the public.

“Moving forward, it will be the responsibility of all elected leaders to take the time to read, study, listen and consider what we can learn from this report and how best to use its information in the interest of the American people,” Golden said in a statement. “We must keep open minds and be respectful of the continuing investigations, some of which stem from the Special Counsel’s work, without jumping to any conclusions.”