What's the group that least agrees with Americans' vision of their country? It's not Muslims, gays, feminists, or recent immigrants. It's atheists, according to many sociological surveys. In one survey conducted in 2006 by sociologist Penny Edgell and her colleagues, nearly half of respondents said they would disapprove if their child wanted to marry an atheist, and a majority would not vote for an atheist president of their preferred political party, the lowest social acceptance rates of any group that Americans are asked about.

It's a little odd that believers would dislike atheists so much, says Will Gervais, a graduate student at the University of British Columbia who did the new study with his advisor, Ara Norenzayan. Atheists are a small minority in America, they are not a visible or coherent group, and most aren't particularly noisy about their beliefs. Previous studies by the same authors have found that the dislike mostly comes from distrust. "It seemed like distrust was driven by the belief that people act better if they feel like they're being watched by God," Gervais says.

So he and Norenzayan decided to explore the relationship between thoughts about secular authority and trust in atheists. The results of this new series of experiments are published in Psychological Science, a journal of the Association for Psychological Science. Distrust among believers declined when people were reminded that God isn't the only authority that keeps people in line -- the government is, too.

In one experiment, Canadian believers were assigned to watch one of two videos: a traveler's story about visiting Vancouver for the first time or the Vancouver police chief's year-end report. These served as a reminder or a prime, to get half the students thinking about the police, who are a source of secular authority. Then participants responded to questions about how much they distrusted various groups, including atheists.

Viewing the video about police effectiveness significantly reduced how much believers distrusted atheists. Other experiments confirmed that this change was specific to feelings about atheists, and didn't come from a general change in attitude towards other marginalized groups.

"Sincere commitment to belief in God may be viewed as a signal for trustworthiness, particularly by religious believers who think that people behave better if they are under supernatural surveillance," says Norenzayan. "Atheists consider their disbelief as a matter of private conscience, while believers think atheists' absence of belief is a public threat to cooperation and honesty. However, this negative perception of atheists declines to the extent that people are reminded of secular means of social surveillance."

"There is evidence that gods and governments can fulfill similar roles," Gervais says. People want the world to be orderly and controlled, but it seems like the authority that keeps people in line can be religious or secular. There's some evidence that when people feel less confident in their government, they're more likely to seek out religion. Norenzayan and Gervais find that in countries where the government is more effective and stronger, atheists are both more common and more trusted.