Marion Superior Court Judge Gary Miller ruled this week that the plate doesn't fall under the rule that requires "special group recognition" plates to carry the added administrative fee.
About 1.6 million Hoosiers have affixed the plates to their vehicles since they were introduced last year, the Indianapolis Star said Friday.
The American Civil Liberties Union had filed the lawsuit on the grounds the fee placed the religious message on a level above plates that support the environment, education or other causes.
Miller's ruling said that the "In God We Trust" plates were made with the same process used to mass-produce the standard Indiana plate and therefore require no special handling fees.
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