U.S. District Judge John Bates said Michael Newdow had no legal basis to pursue his claim because he could not show he would suffer any injury from hearing the prayer.
Bates also ruled that Newdow's claim should be denied because he already had filed and lost a similar lawsuit at a federal appeals court in California last year.
Newdow argued that saying a Christian prayer at the Jan. 20 ceremony would violate the Constitution by forcing him to accept unwanted religious beliefs.
Attorneys representing Bush and his inaugural committee argued that prayers have been widely accepted at inaugurals for more than 200 years and that Bush's decision to have a minister recite the invocation was a personal choice the court had no power to prevent.
