Give people time to act honestly
The Economist explores the psychology of morality by reporting on a dice rolling experiment:
The researchers had no way of knowing what numbers participants actually rolled, of course. But they knew, statistically, that the average roll, if people reported honestly, should have been 3.5. This gave them a baseline from which to calculate participants’ honesty. Those forced to enter their results within 20 seconds, the researchers found, reported a mean roll of 4.6. Those who were not under any time pressure reported a mean roll of 3.9. Both groups lied, then. But those who had had more time for reflection lied less.
The experiment suggests that people who are rushed and don’t take the time to think are more likely to lie and cheat than those who have time to think about their actions rationally.