Despite a flat denial from the Department of Justice, federal law enforcement sources tonight said ABC News accurately reported that Speaker of the House Dennis Hastert is "in the mix" in the FBI investigation of corruption in Congress.

What does "in the mix" mean?

ABC's law enforcement sources said the Justice Department denial was meant only to deny that Hastert was a formal "target" or "subject" of the investigation.

"Whether they like it or not, members of Congress, including Hastert, are under investigation," one federal official said tonight.

How can you be under investigation but not a subject? From the U.S. Attorney's Manual:

A "subject" of an investigation is a person whose conduct is within the scope of the grand jury's investigation.

According to the ABC News report, Hastert wrote a letter urging the Interior Department to reject a proposal for an Indian gambling casino to be built. Shortly before the letter was written, a fundraiser for Hastert that raised $26,000. was held at Abramoff's D.C. restaurant.

Clearly, this would be "within the scope of the grand jury's investigation." For ABC's law enforcement sources to now say all members of Congress are "under investigation" and Hastert "isn't a formal subject" makes no sense.