On the Media in its story "Fact? Check!" forwarded the revelation (uncovered by the PBS program Frontline in the first part of their "News War" series) that the fact that the United States Justice Department launches a leak investigation implicitly confirms the leak! That's because one of the prerequisites for a leak investigation is that the leaked information actually be true.

Lowell Bergman: The information has to be accurate?

Dave Szady: Yes.

Lowell Bergman: So when the government announces a leak investigation and it comes to your office, it's confirming that the report in the newspaper, for example, or on television, was true.

Dave Szady: Yes. Indirectly, yes.

That reminded me of a similar "inadvertent confirmation" from a local news story many years ago. Someone was admitted to the hospital with acute poisoning, and the local newspaper called to determine whether it was an attempted suicide. The hospital confirmed that the person had been admitted, but declined to discuss whether it was due to a suicide attempt. "Our privacy policy forbids us from revealing any further information about patients who are admitted after an attempted suicide."