The glow of green virtue (Image: Nicola Tree/Photodisc/Getty)

Green consumers sometimes take the moral high ground – but it’s all too easy to slide back down. New research suggests that those who make “green” purchases are subsequently more likely to behave selfishly, cheat and steal.

“Another way to think about it is that you’re off the hook – you’ve done your good deed,” explains Benoît Monin, a psychologist at Stanford University in California who studies the phenomenon, called “moral self-licensing”.

Moral self-licensing has been shown elsewhere, too. In the run-up to the 2008 US presidential election, for instance, Monin found that people who expressed their support for Barack Obama, thereby winning credit as non-racists, were more likely to later declare that whites would be better suited than blacks for a hypothetical job vacancy in a police department (Journal of Experimental Social Psychology, vol 45, p 590).


To find out if green consumerism gives people a similar licence to behave badly, Nina Mazar and Chen-Bo Zhong of the University of Toronto in Canada set up experiments in which students were presented with simulated online stores.

Good shop, bad shop

Students were asked to fill their online shopping baskets with up to $25-worth of items, and half were presented with a store stocked mostly with “green” products – compact fluorescent instead of incandescent light bulbs, for instance – to make it more likely that they would shop green. The other half were given a store stocked with a majority of conventional products.

After their online shopping spree, the students were asked to carry out one of two tasks.

One group was told to allocate $6 between themselves and another participant. Mazar and Zhong found that green shoppers in this group kept more for themselves than the others did.

The most striking results, however, came from the group that carried out the second task. Students were shown a pattern of dots and asked to say whether more fell to the left or the right of a diagonal line. They were told they would get half a cent each time they said more dots were on the left, but 5¢ each time they said more were on the right – providing a clear incentive to lie about the results to earn more money.

Those who played the game both accurately and truthfully would make $2.07. The winnings of those who had shopped in the conventional store did not differ significantly from this sum. The green shoppers, however, earned on average 36¢ more, showing that they had lied to boost their income.

Light green fingers

Finally, the volunteers in the second group were shown on screen how much they had won and told to take the right amount of cash from an envelope. Both groups took more than their due, but the green shoppers on average stole 48¢ more than those who had shopped in the conventional store. “It’s a very impressive paper,” says Monin.

It remains unclear how far the moral glow of green consumerism makes people feel they have licence to cheat and steal in the real world. Douglas Medin, a psychologist at Northwestern University in Evanston, Illinois, says that more work must be done to see whether the same thing happens in different situations and cultures.

But moral self-licensing could explain the counterproductive results of some attempts to reduce environmental footprints, such as the recent finding that people in the UK who have made their homes more energy-efficient are more likely to turn up their heating or keep it on for longer.

Journal reference: Psychological Science, DOI: 10.1177/0956797610363538 (in press)