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Mental fatigue doesn’t always make us more likely to act unethically

e’re more likely to do bad things when we’re exhausted. This much-investigated notion has become almost doctrine among ethicists, the broad conclusion of a large and convincing body of research.

But a new study from the University of Washington Foster School of Business demonstrates that exhaustion can actually render us less likely to act unethically in many circumstances—specifically when the act is complicated by a high degree of social consensus that it’s wrong.

In these cases, mental fatigue depletes the energy required to cheat, lie or steal—and keep from being caught. Doing the right thing becomes the path of least resistance.

“Depleted individuals may have less strength to avoid ethical temptations,” says Xiao-Ping Chen, a professor of management at Foster. “But, by the same token, they have less energy to engage in any unethical behaviors that require substantial cognitive effort to commit.”

Co-author Kai Chi (Sam) Yam, a Foster doctoral student, puts it even more simply: “Tired people lack the mental resources to cheat on important stuff.”

Too tired to cheat?

The conventional wisdom on the relationship between fatigue and ethics follows a sound line of logic. When you are mentally and physically tired, your will power is depleted. When will power is depleted, you are more vulnerable to the temptations of cheating, lying and stealing (among other ills).

But this reasoning struck the authors—Yam, Chen and Scott Reynolds, an associate professor of business ethics—as missing some important context. Isn’t it possible, they wondered, to be too tired to cheat?

To find out, they designed three studies to assess the effect of “ego depletion”—a state of cognitive fatigue—on ethical decision making.

The first study developed cognitive fatigue in a set of participants by asking them to write about themselves without using the letters A and N, and primed their ethicality by having them read news stories in which cheating was either accepted or unaccepted socially. Then, after attempting to solve unsolvable math problems for money, the subjects were given the opportunity to fudge their results. Fatigue, combined with a lax social attitude toward cheating, led to more unethical behavior among these subjects. But the same fatigue in the context of a strict social attitude against cheating actually led to less unethical behavior.

A second study surveyed tax accountants during the busy tax filing season to find out whether their relative sleeplessness had an effect on the frequency—and flagrancy—of fraud. Exhausted accountants reported being more likely to leave out data in their reporting—the milder sin of omission that is largely overlooked. But they were less likely to falsify data—a far more serious sin of commission that carries serious consequences.

A third study, of mentally taxed students offered a chance to cheat, came to the same conclusion: Cognitive depletion increases your vulnerability to ethical temptation only when you are a. unlikely to get caught, and b. unlikely get in trouble even if you are caught.

But when the chance and ramifications of being caught in an unethical act are more serious, fatigue becomes a deterrent.

Social consensus

The key variable in this is social consensus—whether or not people care strongly about an ethical standard or rule or law. Do we stand unified in condemnation of an unethical act, or shrug our shoulders and acknowledge that everybody does it?  Do we impose significant penalties, or look the other way?

Chen offers an illustration of the variable effect of social consensus from her native China, where a CEO caught falsifying his resume is given a pass if he is competent. In the United States, on the other hand, the same exposed CEO would immediately resign in shame. “The difference,” she says, “is that the US has a high degree of social consensus that doctoring resumes is wrong.”

Domestically, Chen asserts that the unethical lending practices that led to the collapse of the real estate market and ensuing financial crisis a few years ago may have been sustained by lax ethics at the banks, and exacerbated by crazy schedules.

“People in the industry are known for working really hard. And the ethical standard for lending in 2008 was pretty low,” she says. “So in their depleted states, employees of lending institutions were more likely to engage in practices that we now come to see as unethical and unsustainable.”

The ethical workplace

The authors stress that their study’s finding does not give organizations license to exhaust their employees as a twisted means of promoting ethics.

It simply acknowledges the inevitability that workers will be physically and mentally tapped at times. And it is then that they are most vulnerable to unethical behavior—unless the organization has created a culture that strongly promotes ethical behavior and castigates cheats.

“The important message is that managers need to be highly ethical people and organizations should create cultures that value integrity and honesty,” Chen says. “Then, even when depleted from overwork, their employees will be less likely to engage in unethical behaviors.”

Ego depletion and its paradoxical effects on ethical decision making” is forthcoming in the journal Organizational Behavior and Human Decision Processes.