New research suggests non-religious defendants are penalized for taking secular oaths

A defendant who doesn’t swear an oath to God is more likely to be found guilty by a jury composed of people who do. That finding, published this week in The British Journal of Psychology, upends the entire notion of justice under the law and provides a compelling reason for why we ought to get rid of unnecessary religious oaths entirely.

In Britain, as in the United States, witnesses in a trial are told to place a hand on the Bible and say something akin to, “I swear by Almighty God that I will tell the truth, the whole truth, and nothing but the truth.” People who aren’t Christian, however, can always offer a secular affirmation. It’s the same idea minus the reference to God. The same rule also applies to members of a jury.

Without going into every detail of the paper, the research conducted by England-based researchers Ryan McKay, Will Gervais, and Colin Davis found that certain people equate a religious oath with credible testimony. Consequently, those people are less likely to trust someone who doesn’t swear to God to tell the truth.

In one experiment, faced with a hypothetical situation, people with no religious affiliation were equally likely to say a defendant was guilty whether that person took a religious oath or secular affirmation. (That’s on the left side of the chart below.) But among people who are religious, they were more likely to deem someone guilty if that person took the secular affirmation option. (That’s on the right.)

While there are all kinds of variables that might play into that discrepancy, the researchers attempted to minimize those effects. They also raised this question:

In 2011, 12,152 defendants were convicted by juries in the Crown Court in England and Wales, while 5757 were acquitted by jury verdict… How many of the 12,152 convicted defendants might have been acquitted if there had been no jurors biased against the affirmation?

They attempted to answer it, too:

… If all convicted defendants had been tried by oath-taking jurors, however, we can estimate… that 5665 of the convicted defendants had chosen the oath and 6487 the affirmation… in which case bias against affirming defendants would have resulted in 822 additional convictions in the space of a single year.

Even if that’s speculation, the idea that anyone could be found guilty because he didn’t play along in some religious ritual should be one too many. The way to fix the bias is to eliminate the oath entirely so everyone’s on an equal playing field.

Humanists UK, which has advocated for the elimination of a courtroom oath, sees two paths forward:

One solution is to abolish the oath entirely and just allow secular affirmation: ‘I solemnly, sincerely and truly declare and affirm that the evidence I shall give shall be the truth, the whole truth and nothing but the truth.’

Another is, in addition to requiring everyone to make a secular affirmation, to allow religious people to swear an oath in private in front of court officials who have no connection to the judge or (other) jurors. Some people argue that swearing a religious oath makes religious people more honest. Humanists UK knows of no evidence for that, but this solution should satisfy those who believe this to be true.

The bottom line is that people should never be in more legal jeopardy because they also happen to be non-religious. The idea that someone could be locked up because of unconscious bias is a travesty to justice.

The paper notes that there was a proposal to abolish the oath in England and Wales was floated in 2013, but it was rejected because supporters of the religious oath argued “it strengthens the value of witnesses' evidence.” If that’s true, though, that’s the reason it ought to be abolished. The study concludes:

… Otherwise, non-religious defendants who choose to affirm, rather than “tell a lie” and swear an oath in bad faith, may be taking a risk—“subjecting themselves to a disability”... Ultimately, continued use of the oath may make justice more difficult to obtain for those who are unwilling to swear by a God they do not believe in.

Considering that previous research has shown how people distrust atheists to begin with, there’s no good argument left for keeping the oath in place. At least not if you actually care about justice and equality under the law.