Why Night Owls Are More Ethical In The Afternoon

A new study follows up on the morning morality effect, showing that your ethics is tied to if you are a morning or night person.

Why Night Owls Are More Ethical In The Afternoon
[Image: Flickr user Thomas Rousing]

Whether you are a morning person or a night owl might dictate what time of day you should make your ethics-testing decisions.


It turns out the time of day you feel least productive and alert is also when you’re most likely to lie. A new study by Christopher M. Barnes of the University of Washington’s Foster School of Business, Brian Gunia of Johns Hopkins University’s Carey Business School, and Sunita Sah of Georgetown University’s McDonough School of Business, shows morning people become more unethical at night, while night owls are more unethical during the day.

The full report will be published in Psychological Science later this year, but the researchers posted their findings in a Harvard Business Review blog post.

The researchers wanted to follow up on a previous study on the “morning morality effect” that asked whether people are more moral in the morning than the afternoon and concluded that the day’s events depleted our self-control and our capacity to resist moral temptations, causing us to become liars and cheaters later in the day.

While the researchers felt this seemed to make sense for morning people, they wondered whether the same was true for evening people. “In order to behave ethically, that requires energy,” says Gunia. “Morning people certainly lose energy as the day goes on as the morning morality effect would indicate, but the opposite is true of evening people [who] become more energetic in the evening.”

The team suspected the factor that influenced moral behavior wasn’t a long day of work, but whether we are larks or owls. This is impacted by our natural circadian rhythm, which regulates sleeping habits. “Each of us is born with a tendency toward a particular circadian rhythm,” says Gunia. In short, how ethically one performs at any given point in the day will simply depend on how they’re wired.


To test their theory, they conducted two experiments. The first study was held in the morning only. The researchers asked a group of MBA students to complete a set of math problems and report to the researchers how they did. They were told they would be paid for each problem answered correctly, giving them incentive to lie. Students who reported themselves to be owls were more likely to lie in the morning test than students who identified themselves as larks.

In the second experiment, participants were divided into a morning or evening session and were asked to roll a dice and report to the researchers the number they rolled. The number would be linked to the amount they would be paid (the higher then number, the higher the pay). Those who identified themselves as larks reported more dots in the evening than in the morning, proving that they were cheating more in the evening, while owls reported more dots in the morning.

“Ethicality depends on both time of day and chronotype,” says Gunia. The researchers hope managers use these findings to structure work in a way that best fits employees’ characteristics. “If you want to encourage ethical behavior it’s important to match the person to the situation so morning people should be making their most ethically-fraught decisions in the morning. Evening people should do that in the evening,” he says. Asking a morning person to attend a late-night meeting that requires them to make ethics-testing decisions runs the risk of encouraging unethical behavior.

Changing The Way You Structure Your Day

Similarly individuals should consider how they structure their day and schedule their major decisions around the time of day when they feel the most energized. “Your self-regulatory resources are like a muscle. They can get weaker or stronger in the moment if you have to do something that’s taxing. You want to try to make ethical decisions at a time when that self-regulatory muscle is at its strongest,” says Gunia.

But what do you do if you’re an owl and your boss continues to schedule 8 a.m. meetings? There is evidence to suggest you can use light manipulation to change your behavior patterns. To become more of a morning person and get to bed earlier, Gunia says exposing yourself to bright blue light early in the morning and avoiding this light in the hours leading up to bedtime can help. Similarly, to become more of a night owl, exposure to bright blue light in the evening and avoiding it in the morning is key.


About the author

Lisa Evans is a freelance writer from Toronto who covers topics related to mental and physical health. She strives to help readers make small changes to their daily habits that have a profound and lasting impact on their productivity and overall job satisfaction.