Will Rogers once said that “The income tax has made liars out of more Americans than golf” and I worry that he was correct. During his confirmation hearing to become the Treasury Secretary, it was revealed that Tim Geithner failed to pay Medicare, Social Security, and payroll taxes for several years while he worked for the International Monetary Fund (IMF). When asked by Senator John Kyl (R AZ) during the hearing about the (more than $40,000) “mistake,” which Geithner blamed on the tax software he was using, he replied, “it was very clear that this was an avoidable mistake… You’re right. I had many opportunities to see it.” But he didn’t, apparently, and that was that.

There are many problems here—one of which is the possibility of a double standard that allowed Geithner to get away with this entirely (I am not sure if this is the case or not). I suspect that if he had he been working for a domestic monetary agency, that is, the IRS, he would have faced heavy prosecution, fines, and almost certainly been fired. Also, as the future head of the Treasury, we might hope that he understands the tax code well enough to do his own taxes. Part of his defense, was, of course, that the code is too complex. Which is true, but in light of this, and his own errors, we might then hope he would be more aggressive about reforming the code, which he has not. The worst part of it, however, is the personal example he provided to the rest of the American taxpayers: do your taxes wrong, omit a few things, and if they catch you all you need is to pay it back — it’s basically okay.

I’m not calling for punishing Geithner (retribution isn’t necessarily helpful, not to mention it’s a little late), but as we draw closer to tax time, it’s worth recalling this incident and how it might affect the American public. In the research my colleagues and I have carried out on dishonesty, we’ve found repeatedly that people become more likely to lie and cheat after witnessing the dishonest behavior of others. In one of our experiments, we tested to see how participants would respond to a blatant act of dishonesty in their midst—would they think they too could cheat and get away with it, or would they perhaps straighten up and fly righter than ever? To find out, we gave participants 5 minutes to solve as many mathematical problems as possible (where they were instructed to find which two numbers out of 12 add up to 10).

In the control, where no cheating was allowed, the average student solved 7 problems, which gave them a pay off of $3.50 out of a maximum of $10 (if they solved all 20 problems). To see how witnessing and act of dishonesty would affect participants, we had one student—a confederate named David—stand up after only a minute and claim he’d solved all 20 matrices. The experimenter merely responded that in that case he could take his earnings and go. So how did the participants respond to this display when asked to self-report the number of matrices they solved? By cheating a whole lot: they claimed an average of 15 correct answers, more than twice the average score when cheating was not allowed.

Seeing someone cheat for their own benefit and then get away with it clearly has an impact on our moral behavior—loosening it to a substantial degree.

So, what does this experiment means for paying taxes? It means that the more we see politicians—the people who make our laws—fudge their taxes (which seems to happen continually), the more likely the rest of us are to adjust our understanding of what is right and wrong about paying our taxes, and do the same.

But there is hope. When we ran the same experiment with one slight difference, we found that dishonesty decreased dramatically. This time, instead of looking like all the other participants, who were students at Carnegie Mellon University, we had our confederate wear a sweatshirt that located him within a different social group. This time h was wearing a University of Pittsburgh sweatshirt (Carnegie Mellon’s neighboring and rival university). When the dishonest act was committed by a person from an out-group, we found that cheating decreased dramatically to the lowest level in all the experiments (participants claimed “only” 9 correct problems).

What this means is that if we think of ourselves and our politicians as being part of the same social group, we might follow their footsteps when we hear about another politician or celebrity who hasn’t paid taxes in years. On the other hand, if we don’t think that we belong to the same social group we might not feel more justified in our own moral indiscretions, and instead be extra careful not to be confused with this other, not so moral, social group.

So the moral of the story is: when you settle in to work on your taxes in the next few weeks, try not to think about the individuals who cheat on their taxes—and if you can’t avoid thinking about them, at least try to separate your own social group from theirs.

Go forth and be financially virtuous.

Dan Ariely is the James B Duke professor of Psychology and behavioral Economics at Duke University and the author of (the soon to be released) The Honest Truth About Dishonesty.