Senator Thom Tillis, Republican of North Carolina, who introduced the other measure, said his concern was more about checks and balances than any particular action by Mr. Trump. Legislation, he said, would “lower the temperature” around the investigation and buy Mr. Mueller time and space to finish his work.
“We are not here to clip any one president’s wings, but to create a check on any future presidents,” Mr. Tillis said.
The two bills share much in common, and both try to build on the existing Justice Department statute governing special counsels to ensure that any firing is for good cause.
Mr. Graham’s bill, introduced with Senator Cory Booker, Democrat of New Jersey, would require the attorney general — or a deputy — to petition a panel of federal judges for permission to remove a special counsel.
Mr. Tillis’s bill, in contrast, would allow for a judicial review process after a special counsel is fired. The attorney general would have to prove good cause for removal, and a panel of three federal judges would have 14 days to reach a decision. The bill was introduced with Senator Chris Coons, Democrat of Delaware, and a bipartisan pair of representatives have introduced parallel legislation in the House.
Mr. Mueller was appointed in May, after the firing of the F.B.I. director, James B. Comey, and was given broad latitude to investigate Mr. Trump and his associates. But the statute under which he was appointed affords Mr. Mueller, or other future special counsels, few formal job protections. If he wished, Mr. Trump could order top Justice Department officials to fire Mr. Mueller.
Supporters of the Judiciary Committee measures repeatedly alluded on Tuesday to comments and actions made by Mr. Trump about the investigation that they said made their work necessary. Most saliently, in a late-July interview, Mr. Trump told The New York Times that Mr. Mueller’s team was rife with conflicts of interest and warned that investigators would be crossing a red line if they began to look at Trump family finances beyond any relationship to Russia.
Separating themselves from the Republicans, committee Democrats said those comments, and Mr. Trump’s repeated hostility toward investigators, made the need for action urgent.
“Simply put, I have strenuous concern about President Trump’s respect for the rule of law,” Senator Dianne Feinstein of California, the committee’s ranking Democrat, said in an opening statement. “The president must know that Congress will not stand idly by if he attempts to undermine independent criminal investigations.”
The committee’s chairman, Senator Charles E. Grassley, Republican of Iowa, did not make his leanings toward the bills known, but he made clear in his opening statement that he saw an important role for Congress to oversee special counsel investigations.
The Judiciary Committee is one of several congressional committees investigating Mr. Trump’s links to Russia. The committee’s particular interest stems from Mr. Comey’s firing, but it has outlined a broad investigation into several other matters, from the Obama Justice Department’s handling of the Hillary Clinton email case to Mr. Trump’s presidential campaign.
Tuesday’s discussion frequently returned to a 1988 Supreme Court case that weighed the constitutionality of the now-expired independent counsel statute, put in place after the Watergate scandal. In the ruling, the court voted 7 to 1 that the counsel statute did not violate the separation of powers doctrine and was therefore lawful.
But the decision came with a powerful dissent from Justice Antonin Scalia, which in the years since has gained a widespread following.
Independent counsels, such as Kenneth W. Starr, had considerably broader powers and more latitude than today’s special counsels, but the constitutional scholars and members of the committee repeatedly used the decision and the dissent to make arguments for and against the constitutionality of the proposed protection bills.
Senators Ted Cruz of Texas and Mike Lee of Utah, both Republicans, appeared most skeptical that the bills were constitutionally supportable.
“The overriding concern I have whenever we are talking about this area is that bad things happen when we depart from the three-branch structure of the federal government,” Mr. Lee said.
Akhil Reed Amar, a law professor at Yale, told the panel that he expected either measure could be vetoed by the president or invalidated by the courts. Other legal scholars disagreed.
Continue reading the main storySource: New York Times – Politics