I found this paper fascinating.
The FBI’s Role in the Pearl Harbor Attack(.pdf)
However, mounting new evidence clearly demonstrates not only that the Pearl Harbor commanders shouldered the blame unjustly but that the FBI secretly and shamelessly contributed to this result. Specifically, the FBI successfully: (1) shielded investigation of its own failures from all Pearl Harbor investigations; (2) acquiesced to the Commission Chairman’s perjury to Congress; (3) secretly influenced Congress’ report to protect the FBI at the expense of the Army and Navy; (4) secretly made false accusations against Admiral Kimmel and General Short; and (5) conspired to withhold evidence from the Attorney General.
Just another example of the sort of dirty bureaucratic games that Hoover played every day he was with the Bureau. That's old news but the article shows that Hoover's lies and distortions still color the historical record.