offense or to defraud United States?
According to John Dean:
There are stories circulating that Rove may have been told of Valerie Plame's CIA activity by a journalist, such as Judith Miller, as recently suggested in Editor & Publisher. If so, that doesn't exonerate Rove. Rather, it could make for some interesting pairing under the federal conspiracy statute (which was the statute most commonly employed during Watergate).
Section 371. Conspiracy to commit offense or to defraud United States
If two or more persons conspire either to commit any offense against the United States, or to defraud the United States, or any agency thereof in any manner or for any purpose, and one or more of such persons do any act to effect the object of the conspiracy, each shall be fined under this title or imprisoned not more than five years, or both.
If, however, the offense, the commission of which is the object of the conspiracy, is a misdemeanor only, the punishment for such
conspiracy shall not exceed the maximum punishment provided for
such misdemeanor.
http://writ.news.findlaw.com/dean/20050715.html