Updated

A retired Army sergeant in Detroit was refused a vanity license plate with the word "INF1DL," because Michigan's Department of State determined that the word may carry a connotation offensive to good taste or decency under the Motor Vehicle Code guidelines.

Michael Matwyuk, who served 22 years in the Army and fought in Iraq, recalled how fellow soldiers eventually embraced the word "infidel," which they were oftentimes referred to by enemy fighters. These soldiers, he said, would celebrate the term and stick the word on clothes and even tattooed the word on their bodies.

Matwyuck, who suffered a traumatic brain injury and hearing loss, says the rejection has infringed on his First Amendment right and has since teamed with the American Civil Liberties Union of Michigan to fight the decision.

"A message on a vanity license plate may be brief, but that doesn’t mean there are fewer constitutional protections," Dan Korobkin, an ACLU attorney, said. "The "good taste and decency" standard can be interpreted at the whim of officials in charge at any given moment and therefore it's anybody’s guess what message will survive the review process. This subjectivity is exactly what our First Amendment was designed to guard against."

The complaint, which was viewed by FoxNews.com, says Matwyuck seeks a declaratory judgment, permanent injunction, and compensatory or nominal damages.