Given the recent increase observed in crime and violence related to sport activities and the subsequent need for governments to devote more resources to deter this pattern, this article presents empirical evidence that could justify the possibility of taxing the negative externalities associated with the staging of football matches. Focusing specifically on theft (mainly pick pocketing) and assault (interpersonal violence or hooliganism), we seek to determine the extent to which this private leisure activity is responsible for negative crime externalities on a urban context. Drawing on data for the matches played by Football Club Barcelona (FCB) and geocoded crime data for the city of Barcelona (Spain), we assess whether there is an increase in thefts and assaults across the city of Barcelona. Then, conducting an Exploratory Spatial Data Analysis (ESDA) and a spatial regression at the census tract level, we determine the effect of football matches on crime by comparing crime rates during home and away matches. We find an increase in the number of thefts across the whole city but, especially, in those census tracts within a 700-meter radius of the stadium, indicating that despite the increase in the number of police officers on duty in the vicinity of the stadium, potential offenders are attracted to crowds where rewards are likely to be higher and the probability of being apprehended lower. These results are confirmed by the relatively low number of crimes committed during away matches in the census tracts around the stadium. A similar spatial pattern is found for assaults, although the overall impact across the city is not significant. Our results, therefore, provide evidence of a displacement effect of violent supporters (hooligans) towards the census tracts closest to the FCB stadium on football days. JEL Codes: K42, H27, R1, L83