A new study cited by George Monbiot in his Nov 9th column finds that after purchasing “green products” consumers are more likely to in engage in what’s called “moral licensing” – the idea that the moral self-esteem boost associated with “buying green” is used to justify less ethical behaviour in other circumstances.

From the article:

“Psychologists at the University of Toronto subjected students to a series of cunning experiments. First they were asked to buy a basket of products; selecting either green or conventional ones. Then they played a game in which they were asked to allocate money between themselves and someone else. The students who had bought green products shared less money than those who had bought only conventional goods…

…Then they took another bunch of students, gave them the same purchasing choices, then introduced them to a game in which they made money by describing a pattern of dots on a computer screen. If there were more dots on the right than the left they made more money. Afterwards they were asked to count the money they had earned out of an envelope.

The researchers found that buying green had such a strong licensing effect that people were likely to lie, cheat and steal: they had established such strong moral credentials in their own minds that these appeared to exonerate them from what they did next. Nature uses the term “moral offset”, which I think is a useful one.”

See also this paper from researchers at the University of Toronto on the subject; and these reflections on Monbiot’s piece by Raj Patel at Commondreams.org.