Intimidating people to lie for you or simply coerce them to tell the lies you want them to tell is Rove's specialty.

Working for a family with long standing CIA ties makes this a rather easy job. What ever dirt you want, you can get.
Threatening the well being of a wife or girlfriend is one of the first things even the FBI will do to extort co operation. Its standard operating procedure.

That Rove is caught in a web by a law first proposed By W's father is the height of irony. That he will get off by saying "I didn't know" is very Reaganesque.