Is the gender gap theory in criminology valid for substance abusers who have been imprisoned? We analyzed the risk of committing a crime between 2006 and 2010 using a Cox regression analysis. The data from Finland consisted of 2,034 women and 4,537 men substance abusers divided into groups based on prior imprisonment. Overall, men had a greater risk of committing any crime than women did. However, the gender gap hypothesis was not valid in the specific case of property crimes in a substance-abusing population with prior incarcerations. Women with prior convictions differ profoundly from other substance-abusing women. This raises a question if imprisonment had a wider marginalizing effect on women than on men.