Moussaoui Death Penalty in Jeopardy

The prosecution needs to prove, beyond a reasonable doubt, that FBI higher-ups would believe, and act on,
the testimony of a man sworn to destroy America

while, at the same time, they would not believe, and act on,
the impassioned warnings of faithful freedom-loving career agents who reported suspicions of the terrorist plots.

The "would believe Moussaoui and not agents" part is easy to accept;
the "would act on" part is the hard-sell.