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Morning and Night People More Ethical at Different Times of Day

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When hiring new talent, employers consider candidates’ ethicality as one of the most attractive and desirable qualities. However, managers often fail to realize that an individual’s ethicality can depend on the time of day.

In a forthcoming article in the journal Psychological Science, titled “The morality of larks and owls: Unethical behavior depends on chronotype as well as time-of-day,” Georgetown McDonough Assistant Professor Sunita Sah and her co-authors investigate the fit between an individual’s chronotype and the time of day as a predictor of ethicality. The study challenges the existing “morning morality effect” – the belief that people are more moral in the morning. The effect claims that ethical decisions are mentally taxing, and that normal daytime activities deplete individuals’ limited cognitive resources as the day goes on. Therefore, individuals are more likely to be unethical as the day wears on due to a loss of energy and effort to exert self-control and behave ethically.

To challenge this effect, Sah and her co-authors considered the two processes of sleep – circadian (cyclical fluctuations in sleep propensity) and homeostatic (people’s sleep propensity while awake) – and researched the relationships between a person (chronotype) and the situation (time-of-day). Sah labeled the chronotype of morning people as “larks” and evening people as “owls” with larks usually getting up early, and owls usually staying up late.

“Our ethical values are not fixed,” said Sah. “Instead, we exhibit behavior patterns with varying levels of ethicality across the day based on our circadian rhythms. By understanding our chronotypes, we can help predict when ‘the better angels of our nature’ will appear.”

Through experiments involving rewards based on the completion of matrix tasks and values of rolled dice, the researchers discovered that larks in the night session were more likely to be unethical than larks in the morning sessions, and owls in the morning session were more likely to be unethical than owls in the night sessions – suggesting that individuals may be more likely to act unethically during the ‘mismatched’ time of day.

“Sleep can have a significant impact on ethical decisions,” said Sah. “Our research suggests that early-rising owls or late working larks will be more likely to make seemingly small, unethical decisions that could have larger consequences.”

To mitigate this risk, managers should learn the chronotype of employees and create work structures, schedules and hours that match individuals. Employers who require larks to make challenging, ethical decisions at night or owls to make similar decisions in the morning, run the risk of encouraging unethical behavior. Employers should also carefully consider overtime, shift work, flextime and requirements during Daylight Savings Time clock changes.

Similarly, individuals who control their own work schedules should be cognizant of chronotypes when structuring their work day. Larks should reconsider working overtime into evening hours while owls should be cautious when waking up earlier to get a head start since resisting temptation may be harder during these ‘off’ times of day. This may include more consideration when taking naps or prolonged breaks from work.

“By understanding their chronotypes and the significance of the time of day, individuals can become more ethical in the way they work, the quality of their work and the decisions they make,” said Sah.