This study examines the differences in the personality traits of polydrug addicts (functionals and chronics) as a function of whether or not they had been involved in delinquent behaviors. An assessment protocol, which comprises the European Addiction Severity Index (EuropASI), the Reduced NEO Inventory (NEO-FFI), and the International Personality Disorder Examination (IPDE), was administered to 320 drug addicts of both sexes, of ages between 17 and 60 years. The results showed that the functional consumers who had previously been charged with crimes scored higher in the schizoid, dissocial, borderline, and histrionic traits of personality disorders than the consumers who had not been charged. In the chronic drug-addicts, individuals who had been charged with crimes scored higher in the normal personality dimensions related to extraversion and openness to experience. With regard to personality disorder traits, only the dissocial trait was significant when this group was compared with drug-addicts who had not been charged. The establishment of an adequate description of drug-addicts by typologies, as well as with the elaboration of personality profiles in which their participation in criminal actions is taken into account implies an in-depth study in order to apply more efficient strategies to modify their dysfunctional behavior.