(CN) - Iowa cannot make it illegal for Amish drivers to use steel wheels on their tractors, the state Supreme Court ruled.
Members of the Old Order Groffdale Conference Mennonite Church are limited to driving tractors that have steel cleats on the wheels.
But Mitchell County officials outlawed these wheels with a road-protection ordinance passed in fall 2009 against tractors "equipped with cleats, ice picks, studs, spikes, chains or other projections of any kind."
Church member Matthew Hoover Zimmerman was cited in February 2010 for driving his tractor with steel "lugs," the bars that make contact with the highway.
After a magistrate upheld the citation, Zimmerman appealed the case.
In Mitchell County District Court, fellow church member Eli Zimmerman testified that the church's insistence on the steel lugs stems from Romans 12:2.
"And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God," the passage states.
Eli Zimmerman explained that the bars are to ensure the tractors are used for work and not in place of the traditional horse and buggy. Members who violate this rule would be barred from the church, which also prohibits the use of radio, television and computers.
Mitchell County officials testified that the steel lugs have damaged county roads because they are harder than some of the elements in the road surface.
The district court affirmed the magistrate's opinion, leading Zimmerman to appeal to the Iowa Supreme Court, which reversed on Feb. 3.
"Although the issue is a close one, we conclude the ordinance as applied to church members violates the Free Exercise Clause of the United States Constitution," Justice Edward Mansfield wrote for the court.
Aside from Amish tractors, school buses use ice grips and tire studs without issue.
"We also find the ordinance does not survive strict scrutiny because it is not the least restrictive means of serving what is claimed to be a compelling governmental interest in road protection," Mansfield added.
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