Wear a dark coloured jersey and get ready to reap more penalty minutes, according to a new study. Published in Social Psychological & Personality Science, researchers found that hockey teams wearing dark jerseys were more likely to be penalized.
Researchers analysed 50,000 NHL games over a quarter of a century. Thanks to 2003’s rule change, which made teams wear coloured jerseys at home and whites for away games, generally the opposite of what had happened before, researchers were able to correct for the effect of a friendly crowd on the number of penalty minutes awarded.
Generally, teams in black received 10% more penalty minutes than teams in other colours.
According to researchers, three possibilities exist to explain the phenomena. Players wearing darker colours may be more visible, players wearing darker colours could be more aggressive, or referees may have an unconscious bias against players in dark colours.
The last explanation may be the best; in an earlier study, researchers had high school football players run two identical versions of players, only varying uniform colour. Referees who were later showed videos of the plays called more fouls on the players who wore black.