The first amendment of the United States constitution guarantees freedom of religion. However, officials in Maine initially refused his plea to update his licence photo.
Even the American Civil Liberties' Union was reluctant to take up the cudgels on behalf of Moonsong, declining to fight his case.
Undaunted he sent in an essay in which he set out the symbolic importance of the horns for a pagan priest and the state relented.
"It is our policy to follow the guidelines set out by American department of motor vehicle administrators," a spokesman for the state of Maine said.
"It is a policy which does not allow hats or head coverings. But he said it was for religious purposes, which is one of our exceptions. As it did not cover his face we allowed it."
This article was originally published by Daily Telegraph