Cam Simpson reports on the Rod Blagojevich case in Chicago.

Conventional wisdom holds that U.S. Attorney Patrick Fitzgerald ordered the FBI to arrest Rod Blagojevich before sunrise Tuesday in order to stop a crime from being committed. That would have been the sale of the Senate seat vacated by President-elect Barack Obama.

But the opposite is true: Members of Fitzgerald’s team are livid the scheme didn’t advance, at least for a little longer, according to some people close to Fitzgerald’s office. Why? Because had the plot unfolded, they might have had an opportunity most feds can only dream of: A chance to catch the sale of a Senate seat on tape, including the sellers and the buyers.

The precise timing of Tuesday’s dramatic, pre-dawn arrest was not dictated by Fitzgerald, nor was it dictated by the pace of Blagojevich’s alleged “crime spree.” It was dictated by the Chicago Tribune, according to people close to the investigation and a careful reading of the FBI’s affidavit in the case.

At Fitzgerald’s request, the paper had been holding back a story since October detailing how a confidante of Blagojevich was cooperating with his office.

CAROLINE WANTS HILLARY’S SEAT