Josh Gerstein of the New York Sun is always must-read. Today he reports on FBI leak case files that have apparently up and vanished:

The FBI is missing nearly a quarter of its files relating to investigations of recent leaks of classified information, according to a court filing the bureau made last week.

In response to a Freedom of Information Act lawsuit, the FBI said it identified 94 leak investigations since 2001, but that the investigative files in 22 of those cases “are missing” and cannot be located. “There is no physical slip of paper on the shelf which indicates that the file has been charged out to a particular FBI employee, so therefore there is no way of knowing where the file may actually be,” an official in the bureau’s records division, Peggy Bellando, wrote in a December 22 declaration.

“That’s an amazing number,” an academic who has studied the FBI’s record-keeping procedures, Athan Theoharis of Marquette University, said in an interview yesterday. “These are very sensitive investigations. … They could be called to account for whether they are monitoring reporters. These are records that should be handled very well.”

Better order some pants and socks checks pronto.