In a study by Kouchaki and Desai (2015), employees who reflected on the importance of ethical behavior were found to be less likely to engage in unethical behavior.
To create the conditions for such reflection, companies often provide off-the-shelf ethics training. Unfortunately, most employees find the traditional online modules to be relatively boring (and the end-of-module quiz too easy).
Perhaps a more engaging approach is to provide employees with opportunities to discuss real-world ethical dilemmas. A quick look at the morning news should offer several examples of cheating, lying, and stealing. Any supervisor can start a discussion with this phrase: “This just happened at Company X. Could it happen here? If not, why? If yes, how could we respond differently?”
Doing this on a regular basis is sure to align the moral compass of most employees. Give it a shot.