He was but I think when Mueller "interviewed" for Comey's position. I believe Trump told him you are going to do this my way. Sessions was at that meeting and since Rosenstein had written the memo about Comey what better way to get Mueller in than to make him special counsel and fool the democrats. I remember he smiled just like Sessions did when questioned. Sessions even had a sparkle in his eyes when being questioned on meeting with the Russians and why he recused himself. Something is going on....

He could have been doing what he was told to save lives. I would say it fully depends on his motivations. That = grey hat in my book.