The firing of FBI deputy director McCabe was, according to AG Sessions, based on McCabe’s lack of candor relating to an inquiry of his handling of the Clinton Foundation. As part of the inquiry, McCabe was questioned about conversations FBI officials had with a reporter in October 2016 regarding the FBI's investigation of the Clinton Foundation. The inspector general's report, which has not been made public, reportedly concluded that McCabe was not completely candid in answering questions about those conversations, according to officials familiar with the report.
During his Senate confirmation hearings, Sessions clearly stated that he would recuse himself from any issues regarding both the Clinton campaign and the Clinton Foundation:
Grassley: During the course of the presidential campaign, you made a number of statements about the investigation of former Secretary of State Hillary Clinton, relating to her handling of sensitive emails and regarding certain actions of the Clinton Foundation. You weren’t alone in that criticism. I was certainly critical in the same way as were millions of Americans on those matters, but now, you’ve been nominated to serve as attorney general. In light of those comments that you made, some have expressed concerns about whether you can approach the Clinton matter impartially in both fact and appearance. How do you plan to address those concerns?
Sessions: Mr. Chairman, it was a highly contentious campaign. I, like a lot of people, made comments about the issues in that campaign. With regard to Secretary Clinton and some of the comments I made, I do believe that that could place my objectivity in question. I’ve given that thought.
I believe the proper thing for me to do, would be to recuse myself from any questions involving those kind of investigations that involve Secretary Clinton and that were raised during the campaign or to be otherwise connected to it.
Grassley: OK. I think, that’s—let me emphasize then with a follow-up question. To be very clear, you intend to recuse yourself from both the Clinton email investigation and any matters involving the Clinton Foundation, if there are any?
Sessions: Yes.
Apparently that was a lie.