Crime is negatively correlated with IQ while attractiveness and symmetry are positively correlated so there's one method. Races are outwardly visible and have

Crime is negatively correlated with IQ while attractiveness and symmetry are positively correlated so there's one method. Races are outwardly visible and have different crime rates. Young males overwhelmingly commit most crime, and you can pick them visually apart from old women who commit little crime.