Vohs, K., & Schooler, J. (2008). The Value of Believing in Free Will: Encouraging a Belief in Determinism Increases Cheating Psychological Science, 19 (1), 49-54 DOI: 10.1111/j.1467-9280.2008.02045.x
I've been sitting on this for a while, and I've finally got the discipline together to actually write again. Getting things done! It's just a short post, though.
Anyway, the authors in this study manipulated whether or not subjects were primed with the concept of free will. They did this by exposing people to sections of Francis Crick's book, The Astonishing Hypothesis. (I have to say I haven't read it, but Crick's done some great work on consciousness.) He's a big proponent of biological determinism, or materialism, or whatever you'd like to call it - essentially that behavior is a function of the wetware inside our heads, and that if the inputs can be specified enough the outputs will be strictly determined. Essentially, it's an argument against free will (as normally conceptualized).
A passage from his book arguing this point primed subjects to "reject" the free will hypothesis, while the control group read a passage about consciousness that didn't include anything about free will. After this, subjects completed activities which allowed for a certain degree of cheating (both passive and active cheating were examined in different experiments). The results showed that those subjects who had been primed to reject free will cheated significantly more than those in the control condition.
So what does this mean? The authors argue that having a deterministic outlook makes people less accountable for their behavior - that they're more likely to lay aside the blame for their behavior because they feel they don't have control over it. This has some obvious implications. Is determinism a dangerous idea? Will people who subscribe to this idea start breaking rules because, hey, it's what my brain's making me do? I've had my differences with Clarence Thomas, but paraphrasing one of his quotes here makes a lot of sense: whether free will exists or not is immaterial, but the appearance of free will must be maintained to hold people accountable. Taking determinism to its utmost extent, the belief in free will is just another input that will affect a mechanistic decision making process.