Mueller should be called into Congress to testify -- but AG Barr will have control of what he can say: Ex-Watergate counsel
Robert Mueller testifies before Congress (screengrab)

The lawyer who argued United States v. Nixon in the Supreme Court, Philip Lacovara, told CNN on Monday that Congress should have special counsel Robert Mueller in to testify to his findings -- but cautioned that attorney general Bill Barr will have control over what he's allowed to say.

Mueller "is going to be guided in what he will say by whatever instructions he gets from attorney general Barr," said Lacovara.

"This is another issue on which I have some strong feelings, that Barr himself has a good deal of discretion about how he interprets the concept of grand jury secrecy," he continued, saying the rules were "rather vague."

"I think Bob Mueller will apply whatever standards attorney general Bill Barr instructs him to apply in talking about what he found during his investigation," Lacovara added.

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