because bush knows he broke the law

Gonzales: Bush blocked eavesdropping probe
WASHINGTON - Attorney General Alberto Gonzales said Tuesday that President Bush personally blocked Justice Department lawyers from pursuing an internal probe of the warrantless eavesdropping program that monitors Americans' international calls and e-mails when terrorism is suspected.

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Not the least bit surprising, since bush knows that what he did was illegal and he doesn't want any more attention drawn to his illegal activities.

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