In a June 2018 memo, William Barr reached a decisive and controversial conclusion that Trump's interactions with ex-FBI Director James Comey would not constitute obstruction of justice. A copy of that memo was released to senior Justice officials in December.
Barr had not yet been confirmed as attorney general at the time of the memo release. He discussed the memo with Trump and told him it would likely come up during his Senate confirmation, a source familiar with the discussions told CNN.
Barr has not shied away from defending Trump's firing of Comey, but the June 8 memo offers a detailed analysis of one of the most consequential episodes of Trump's presidency, concluding that while he's "in the dark about many facts," Robert Mueller's obstruction inquiry was "fatally misconceived."
Barr added that Trump asking Comey to let go of the investigation into former national security adviser Michael Flynn and later firing Comey were within his powers as head of the executive branch.
"Mueller should not be able to demand that the President submit to an interrogation about alleged obstruction," Barr wrote. "If embraced by the Department, this theory would have potentially disastrous implications, not just for the Presidency, but for the Executive branch as a whole and the Department in particular."