When Barack Obama announced that he was supporting same- , he cast the discussion in moral terms. The focus of his remarks was on fairness. He pointed out, for example, that there are gay men and women serving in the military who are not free to marry the people they love. That is unfair.

The concept of fairness is a moral value. Why are discussions of issues like gay marriage turned into moral issues? There are many ways that this discussion could have been frame. For example, the President could have focused on the economic benefits for couples to have the option to marry.

One reason by President Obama framed his discussion as a moral issue is that opposition to gay marriage has also been cast in moral terms. Opponents of gay marriage often have strong religious views that make behavior broadly and gay marriage in particular a moral issue. So, Obama was simply fighting one moral value with another.

But that doesn’t explain why everyone feels that an issue like gay marriage should be discussed in moral terms.

An interesting paper by Daniel Effron and Dale Miller in the May, 2012 issue of and Social Psychology Bulletin explores this issue. They point out that the psychological value of creating a moral issue is that it gives people a legitimate reason to have an opinion on an issue.

Most of the time, we give people the right to weigh in on an issue when it affects them directly. If someone threw garbage all over my lawn, it would make sense if I was angry about it in the morning, because my house was affected directly. It would be strange, though, if a stranger walking through the neighborhood got angry about it. After all, she is not affected by the mess. If, however, she turns it into a moral issue, then we, as a community, give her the right to have an opinion about what happened.

In one study, Effron and Miller asked people whether they thought abortion rights was a moral issue. A few weeks later, they asked the same people to read about a man or a woman who advocated strongly in favor of a pro-choice position on abortion rights and donated money to a pro-choice group. They were asked whether they were skeptical, suspicious and surprised about this person’s support of abortion rights. Participants were unsurprised that a woman would be pro-choice. People who thought that abortion is not really a moral issue were skeptical of men who took strong stances on abortion, while those who thought it was a moral issue at heart were not at all skeptical or surprised by a man who took a strong stance. That is, when an issue is seen in moral terms, it gives people the right to have an opinion, even if the issue may not affect them personally.

In another study, the researchers looked at the rights of victims of a minor . They were told about two people whose houses were damaged by vandals. One house sustained $1,000 worth of damage, while the other sustained only $80 worth of damage. In this case, people judged that the person whose house was more badly damaged had more right to be outraged at what had happened. However, other people were told the same story, but in this case, the smaller amount of damage consisted of graffiti that was morally offensive to the homeowner. Once the crime took on this moral dimension, people judged that the person who had sustained less damage was more entitled to be angry.

Putting all of this together, the moral dimension is used to help people participate in community-wide issues. Generally speaking, we expect people to be involved only in issues that have direct relevance to their lives. However, our society cannot function effectively if people are only self-interested. As a result, we turn issues into moral issues to allow us to have discussions that may affect the lives and behavior of other people around us.

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