A Minnesota statute required all operators of slow-moving vehicles to display a fluorescent red triangular sign. Henderson, an adherent of the Amish religion, was charged with violating the statute. His defense was that the law violated his First Amendment right to freedom of religion because displaying “loud” colors on his slow-moving black buggy conflicted with his religious belief that he should remain separate from the modern world. Henderson stated that he was willing to display the sign if he could use silver, instead of red, reflective tape, which was equally effective. The state argued that the law applied to all equally. The court most likely found that the statute, as it applied to Henderson, was: