Crime is unequally distributed with respect to both who becomes involved in offending and the frequency with which these individuals offend. However, we know less about how these properties of the crime distribution have themselves changed over time. In cases where crime levels have changed, have these changes been general, affecting all social groups equally, or have they been more focused on certain social groups? We examine the changing social composition of known offenders using Swedish administrative data to determine whether inequality in offending is increasing or decreasing. Our analyses are based on a multicohort approach. The results show that the proportion of convicted men has decreased. Those who are convicted for crimes have therefore become an increasingly selected group. This has also entailed that they have increasingly come to be made up of groups with less resourceful socio-economic backgrounds, which in turn has fostered a more unequal distribution of crime.