President Trump has directed former White House counsel Donald McGahn to not appear before Congress for the investigation of special counsel Robert Mueller on Tuesday. White House counsel Pat Cipollone wrote that McGahn has certain “constitutional immunity” from obligation to the committee. Cipollone also cited the Office of Legal Counsel opinion on McGahn, which reads:
"The immunity of the President's immediate advisers from compelled congressional testimony on matters related to their official responsibilities has long been recognized and arises from the fundamental workings of the separation of powers. Those principles apply to the former White House Counsel. Accordingly, Mr. McGahn is not legally required to appear and testify about matters related to his official duties as Counsel to the President."
While this may frustrate Chairman of the House Judiciary Committee Jerry Nadler, ABC News contributor Benjamin Siegel reported that such an immunity based on an Office of Legal Counsel opinion is precedented by past administrations — including Barack Obama’s presidency.
“For example, in 2014,” Siegel wrote, “the Obama administration blocked senior adviser and director of the White House Office of Political Strategy, David Simas, from testifying before the House Oversight Committee.”
h/t: abc News