Academics have, for the first time, found firm evidence of a link between domestic violence and 'Old Firm' football matches.
The study, by the University of St Andrews, is the first to confirm long-held beliefs that reports of domestic violence in Glasgow increase following matches between Rangers and Celtic.
The new paper, published online this week, shows a 'statistically significant' increase in domestic incidents following all 21 Old Firm matches between 2008 and 2011.
Researchers say the results of the study provide 'compelling evidence' of the effect of Old Firm matches on reported domestic cases of physical, sexual and emotional abuse in the 24 hour period after kick off.
The study was led by Dr Damien J. Williams, a lecturer in Public Health Sciences at the University of St Andrews.
He said, "Media reports have long suggested that the number of reports of domestic violence appear to increase when Scotland's two largest, Glasgow-based football clubs, Rangers and Celtic (traditionally referred to as the "Old Firm") play one another.
"These have followed concerns by the Scottish Government who say that domestic abuse in Scotland is an increasingly visible problem, with the highest prevalence on females in Strathclyde."
Statistics indicate a year-on-year increase in incidents of domestic abuse reported to the police between 2002 and 2003 (35,877) and 2011 and 2012 (59,847). The majority of these incidents occurred in the Strathclyde Police jurisdiction, with the majority of victims being female.
Dr Williams continued, "However these reports have been based on crude comparisons of limited data sets. Our aim was to develop a robust analytical approach to undertake a preliminary exploration of the association between Old Firm matches and reported domestic incidents in the Strathclyde Police area."
Previous studies have examined abuse of partners by male athletes, while others have looked at the link between sporting events and increased domestic violence – thought to be the effects of the toxic combination of sport, alcohol and heightened masculine behaviour.
In the new study, Dr Williams worked with St Andrews graduate Kirsty House (now at the University of Cambridge) and St Andrews' colleagues Dr Fergus Neville and Professor Peter Donnelly.
The researchers looked at the number of reports of domestic violence incidents to Strathclyde Police following an Old Firm match, including those held on Sundays. Reports were based on any form of abuse against a partner, or ex-partner, in the home or elsewhere.
They then compared the figures with those reported for the same 24 hour period seven days after an Old Firm match and also 24 hours after high-profile Scotland international games (played in Glasgow), which would likely involve similar amounts of alcohol and expression of masculine identity.
Dr Williams continued, "We found a statistically significant increase in the average number of reports following Old Firm matches, compared with other periods. Our preliminary analysis confirms previous speculation concerning the association between Old Firm matches and reports of domestic violence."
The team call for further research to interpret and understand the complex association between sport and domestic violence. Although they did not study reports of domestic violence in relation to match outcomes, disciplinary issues on the pitch, or domestic violence reports before a match, they say these could be worthy topics for future research.
Dr Williams continued, "Our approach may underestimate the true impact of Old Firm matches on domestic violence, as not all incidents are reported to the Police, but it nonetheless offers a conservative estimate of the severity of the problem.
"We hope that our work will not only inform preventive interventions to tackle the association between Old Firm football matches and domestic violence, but will add to the literature advocating for prevention efforts to address sport-related domestic violence more generally. "
Explore further: How will Congressmen vote? Just look at their social circles, study finds
More information: Williams, D. et al. Association Between Old Firm Football Matches and Reported Domestic (Violence) Incidents in Strathclyde, Scotland, SAGE Open. sgo.sagepub.com/content/3/3/2158244013504207