In the Supreme Court case of George Reynolds vs. United States, 1879, concerned an older Mormon living in the Utah Territory under federal laws, was charged with a violation of a federal law forbidding marriage in all federal territories. The practice of multiple marriage couples is a practice common among Mormons of that time period. The United States put into effect a law the restricted multiple marriage couples upon receiving word that Mormons were moving into the Utah Territory.
Since the United States Government was founded on Judeo-Christian beliefs, they frowned heavily on the Mormon practice and used their power to restrict their ability to act on their beliefs. The principle of democracy that is directly applicable to this situation is Equality under the Law. George Reynolds took his case to the Supreme Court in objection that he could not fully pursue his religion. He argued that the first amendment guarantees that persons will be free from any law prohibiting the free exercise of religion.
That no federal law could interfere with a person's religious belief or with actions based on those beliefs. That the federal law was unconstitutional and his conviction should be overturned. In his eyes he was not being treated fairly by the government because of what his religion believed was acceptable. He felt that multiple partner relationships should be allowed and that the United States was out of line in restricting that.
The Supreme Court ruled that the case presented an obvious and compelling need to regulate a question of behavior offensive to public will. The first amendment cannot be used as a shield to protect any person against criminal behavior. This ruling states that the first amendment cannot be used as an excuse to do whatever you want simply because your religion says that's ok to do. Mr. Reynolds is allowed to believe that multiple partners are acceptable, but he is not allowed to practice that belief, according to the law of the United States.
The Supreme Court ruling was quite inaccurate in that they think Mormon beliefs are wrong because they differ from their own beliefs. Because Mormon religion is a minority in this country, the rest of the United States feels that they have the right to regulate how the Mormon religion can and cannot be practiced. Mormons should be allowed to pursue their religion to the fullest extent without causing harm to himself or herself or any other individual. It is not fair to tell them what they can and cannot believe in. That is the same as telling us we should have more wives than just one simply because we believe that is the way it should be. We should be more open minded to other religions besides our own.
Simply because we do not share the same beliefs does not mean that they are wrong. Equality under the law obviously has it's limits. In situations like these the law was put into effect in preparation for the Mormon religious practices. The law was placed there to prevent the Mormons from acting on their religion. That is not equality. Equality is letting them have as many wives as they want.
After all, the woman has to consent to the marriage anyways. If she wants to be the third wife then let her. The Supreme Court was wrong in their conviction and they should have overturned the ruling on the case.