See: Bush says won’t prejudge CIA case, Rove’s role – Yahoo! News
“I have instructed every member of my staff to fully cooperate in this investigation. I also will not prejudge the investigation based on media reports,” Bush told reporters in response to a question.
These quote unquote media reports are the reporter standing outside of the grand jury and stating for the news crews that Karl Rove was the source. This isn’t a speculative statement. It doesn’t get more concrete than this.
A good followup and timeline: Karl Rove is fucked
