Forty-three percent of Americans may think Daylight Saving Time is pointless, but could our annual clock-turning holiday fight crime?

Yesterday morning marked the end of DST, reigniting the biannual debate on why we observe this tradition in the first place. Most coverage seems recycled year to year—as local news anchors give friendly reminders to “spring forward” and “fall back”—peppered with the occasional funny story of a pastor who forgets to reset the clocks in the church bell tower and accidentally wakes up the entire town. (We’ve all been there.)

This year, however, there’s an interesting wrinkle in the discussion—sourced from MIT’s Press Journals site, which posted a study on October 20 on the effects of our annual clock switcheroo on the crime rate.

The paper, dramatically titled “Under the Cover of Darkness: How Ambient Light Influences Criminal Activity,” is actually from 2014—and it analyzes the incidence of major crimes in the weeks before and after DST (the time change that takes place in March, not November).

The study compares crime data from 2005 and 2006 to statistics from 2007 and 2008—after Congress enacted our current schedule of clock-springing and -falling.

Researchers Jennifer Doleac and Nicholas Sanders find that “daily cases of robbery … decrease by approximately 7 percent in the weeks after DST begins.” In the evening hours before sunset, the difference is even more striking: They estimate a “27 percent decrease in the robbery rate.”

(This isn’t the first study to draw a criminal connection to DST. Doleac and Sanders note that in 1974, an observational study “suggested violent crime fell 10 percent to 13 percent in Washington, D.C., during the affected time of year.”)

The national decrease in robberies Doleac and Sanders uncovered isn’t just a statistical novelty.

Since 2007, the researchers estimate that DST has saved “$246 million in social crime costs per year, a nationwide social savings of $12 million per hour of additional ambient light during high-crime hours.”

The duo believes Daylight Saving Time deters criminals in three ways:

More light makes criminals easier to spot (seems obvious enough), DST boosts evening foot traffic (more traffic means more witnesses), and Criminals have to adjust their schedules, too—which “might make them unavailable to commit crime” due to “later family dinners or sports practices.”

(The last reason doesn’t sound very scientific, does it?)

Despite the observable effect on robberies, Doleac and Sanders are careful to note that DST may still have its downsides—disrupting circadian rhythms of students and increasing the incidence of “traffic accidents, workplace injuries, and heart attacks” on the first Monday after the switch.

Other vocal critics of DST include the national Parent Teacher Association (PTA), “which expressed concern that children are at risk of being kidnapped while waiting in the dark for a schoolbus.” (The researchers are quick to point out that this alarmist claim is unsubstantiated.)

While Daylight Saving Time continues to annoy the general public, it’s nice to know there’s some upside to the yearly bother.