I think Mitt Romney’s a good, moral man,” Southern Baptist pastor Robert Jeffress told CNN at last October’s Values Voters Summit, “but I think those of us who are born again followers of Christ should always prefer a competent Christian to a competent non-Christian like Mitt Romney.” Numerous prominent conservatives immediately denounced him for trampling on America’s best traditions of religious tolerance. William Bennett declared at the summit the next morning, “Do not give voice to bigotry.” For such critics, apparently, making an issue of a candidate’s religion violates the principles of our pluralist democracy.

In declaring religion out of bounds, they surely sought not only to protect Romney from the criticism of conservative Evangelicals, but to protect the future Republican nominee, whoever he or she might be, from the religiously based criticism of the left, which has already argued that Rick Perry, Michele Bachmann, Rick Santorum, and others are unsuitable because of their supposedly extreme religious convictions.

I have no interest in defending Jeffress, but I believe his conservative critics went too far in declaring off-limits any consideration of a candidate’s religion. There are at least three reasons voters might choose to weigh a candidate’s religious identity: the tribal, the religious, and the political.

First, the tribal. Human beings are by nature sociable animals. That sociability is expressed most broadly as a fellow feeling for the whole human race, or what the ancients called philanthropy . It is expressed more narrowly as identification with the particular political community to which they belong, or as patriotism. And it shows itself even more narrowly, and is often felt even more passionately, as an attachment to smaller groups within the larger community. Human beings have a strong “love of one’s own,” with “one’s own” ordinarily understood in less-than-universal terms.

It is perfectly natural that group solidarity, or tribal loyalties, should influence our voting. In 2008 many African Americans looked upon the election of Barack Obama with special satisfaction, precisely because he himself was an African American. Few among us would condemn this feeling out of hand. In 1960 Catholics looked on John F. Kennedy’s election with equal satisfaction, and we would be judging them by an unreasonably puritanical standard if we condemned them for counting his Catholicism as a point in his favor. Should Mitt Romney be the Republican nominee, many Mormons will want to vote for him partly because he is one of theirs, and who can blame them?

Some might object that the naturalness of our tribalism does not make it good. Perhaps it belongs to our fallen nature, or at least has been tainted by the Fall. Even if this is true, however, it does not mean that we may not indulge our tribal instincts within reasonable and just limits. Not everything in our present nature that results from the Fall must be utterly repudiated. Man before the Fall did not eat animals, yet this practice is now permissible. Private property is an accommodation to our fallen nature, yet no one would contend that for this reason we must disregard our own economic interests when voting. So it is with the extended self-interest represented in our concern with the prestige of our tribe: We may consider it and act on its behalf when voting, so long as we do not thereby intrude on the rights of others.

Second, citizens, especially those who are most serious about their faith, may reasonably consider the religion of political candidates on religious grounds. They may hope that the election of one of their co-religionists will increase the social prominence of the belief system they hold to be true and of greatest value”not only for themselves but for everyone else. Serious believers cannot be indifferent to whether others accept or reject their religion’s message.

Accordingly, they cannot be indifferent to social conditions that render others more or less open to that message. They will quite reasonably want to promote anything, including having a co-religionist in the office of the presidency, that gives their faith public credibility and effect.

Finally, voters may reasonably take a candidate’s religion into account precisely on political grounds. As journalists and political consultants often say, voters want to be assured that a presidential candidate “shares their values.” Presidents do not merely execute decisions made by others. They are also called to make substantive decisions about the common good, decisions that may leave a lasting mark on the community, for good or ill. Accordingly, responsible voters will consider everything about a candidate that sheds light on his fundamental values, which inevitably influence the political decisions he will make. A candidate’s religion is often a powerful indicator of his deepest moral convictions and hence his understanding of the common good.

Consider the example of one of the candidates at the center of the recent controversy: Mitt Romney. Romney has a mixed record on certain moral issues”such as abortion and gay marriage”that are of deep importance to religious believers and secular liberals. During his Massachusetts political career, Romney presented himself as something of a social liberal. When he began his campaign for president, he seemed to reinvent himself as a social conservative. A secular liberal might argue that while Romney was a politician in a socially liberal state for part of his adult life, he has been a Mormon all of his life. And Mormonism is generally a socially conservative religion. It is likely that his social liberalism was just a concession to a state political culture that he could not hope to change, while his present conservatism is an expression of abiding values that he will bring to the presidency. Therefore, his Mormonism is a reason for liberals not to vote for him. Socially conservative voters could use precisely the same line of thinking to conclude that conservatives can vote for Romney.

Such thinking, of course, does not require any judgment of the truth or falsity of the candidate’s religion. It has everything to do with how religious beliefs, whatever they are, inevitably shape a person’s view of the world and hence how and to what ends he will use his authority. Acknowledging this connection is not bigotry but realism. The responsible voter takes such information into account. It would be foolish not to.

Many of Jeffress’ conservative critics are themselves traditionalists and religious conservatives, and they surely do not exclude religion as completely as their comments on Jeffress suggested. Would they treat as a matter of indifference the beliefs of a professed atheist seeking the presidency? Would they not instead think that questions like abortion and embryo-destructive research will be viewed differently by a person who believes every human life is an accidental by-product of the operations of chance and necessity than by one who thinks that every human life is created in the image of God? Such thinking is perfectly reasonable, and there can be nothing wrong with articulating it openly as a basis for supporting or opposing a given candidate.

To insist that we cannot include their religion among the other criteria used to judge political candidates is inseparable from claiming that religion is irrelevant to the moral and intellectual quality of our public life and culture. This is to say that it makes no difference for a political culture whether its people have one religion or another, or indeed whether they have any religious beliefs at all. Insisting that making an issue of a candidate’s religion violates the principles of our pluralist democracy will deaden our public appreciation of religion’s vital and inevitable role in shaping and guiding our civilization, the preservation of which is supposed to be the goal of conservatives. It will not increase religious tolerance, but it will make voters less able to vote wisely.

Carson Holloway is a political scientist and the author of The Way of Life: John Paul II and the Challenge of Liberal Modernity (Baylor University Press).