Joe Stephens had a fascinating piece in the Washington Post on Friday looking into the “previously secret FBI files” of the late conservative columnist Robert Novak:

Previously secret FBI files reveal that the bureau pursued his sources after reading columns by Novak and his writing partner, Rowland Evans, that were published in The Washington Post in 1983 and again in 1987. Agents also tried to identify the source of classified information that Novak divulged in 1983 on the television show “The McLaughlin Group.”

Though agents conducted interviews, reviewed appointment calendars, requested polygraph tests and considered using an administrative subpoena to obtain phone records, they apparently were unable to confirm the identity of any of the sources.

The revelations are contained in 64 pages of files released Wednesday to The Washington Post in response to an open records request filed after Novak's death in August 2009, at the age of 78. By law, such files become public after the subject of the investigation dies.

As Stephens goes on to note, Novak would later play a central role in “publicly identifying Valerie Plame Wilson as a CIA operative,” leading to a federal investigation and the conviction of Lewis Scooter Libby -- an aide to Vice President Dick Cheney:

The files released this week contain no reference to Wilson's case.