ANN ARBOR, Mich. (Michigan News Source) — Sports betting was legalized by the Supreme Court in 2018, but according to a recent study led by the University of Michigan, this move resulted in a significant increase in violent and impulsive crime before and after sports games.

Researchers from U of M and Rice University analyzed crime data from 2017-2021 and identified an increase in alcohol consumption, weapon-carrying, and violent crimes just before and after a sporting event in states with a legal sports betting market.

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According to the report, crime levels reached highest levels following unexpected game outcomes, such as when underdog teams won.

“There is a sizable increase in crime on game days associated with sports betting, both in states that legalized sports betting and in bordering areas of neighboring states where sports betting remains illegal,” said Wenche Wang in a press release, a co-author on the study and assistant professor of sport management at U of M.

The study found that crime increased between 30%-70% from the start of a game to four hours after the game, with the effects even spilling over into neighboring states without a legal sports betting market. Physical assaults jumped up to 93% after unexpected home team outcomes.

The researchers also found that pre-Covid-19 pandemic, betting-related aggression primarily came from high financial loss, but afterwards, non-financial factors, like a highly stressful game, caused more aggressive incidents.

“Shifts in bettor behavior suggest that legalized areas may be even more vulnerable to heightened aggressive behavior as even games where bettors incur no financial loss could be associated with increased crime,” Wang said.