Grumpy, sleep-deprived judges are apparently harder on convicts the Monday after clocks are sprung ahead for Daylight Savings Time. A new study published in Psychological Science found that sentences handed down on "Sleepy Monday" are, on average, 5 percent longer than sentences imposed for the same crimes on other days of the year.
"We have to accept that judges are human," says study coauthor Christopher Barnes, an associate professor at the University of Washington's Foster Business School. "On Sleepy Monday, they should perhaps hand out fewer sentences or be more conscious of the sentences they hand out."
Barnes and coauthors Kyoungmin Cho and Cristiano L. Guanara used data from the US Sentencing Commission to compare sentences delivered the Monday after daylight savings time, when people are generally working on 40 minutes less sleep than they do on a typical Monday, according to Barnes. They examined all crimes for which a judge imposed jail time and controlled for the seriousness of the offense and the criminal history of the defendant. There was a 5 percent increase in jail time that Monday. "We are confident we can tie this effect to Daylight Savings Time," Barnes says. "There is not likely an alternative explanation."
Barnes has made it a mission to scientifically document the hazards of Daylight Savings Time. He worked on one study showing a 5.6-percent increase in work injuries the morning after and another revealing a 3-to-6-percent uptick in "cyber loafing"—checking personal email and other work-unrelated websites on the day. He feels the annual practice, formalized in the US in 1966, should be scrapped.
The increased irritability of judges is probably felt by anyone else deciding a penalty when sleep-deprived, says Barnes. Bosses, parents and referees, for instance, are likely also more ruthless on less sleep. "We know that when people have less sleep, they are negatively affected emotionally," says Barnes. "We also know they are more sure of their judgement."