The Need to Include Biological Variables in Prospective Longitudinal Studies of the Development of Criminal Behavior

It is a pleasure to welcome the important article by Beckley and colleagues¹ on the association between childhood blood lead level (BLL) and later criminal offending. The authors have analyzed the Dunedin (New Zealand) Multidisciplinary Health and Development Study and have concluded that BLLs at age 11 years are weakly associated with convictions and self-reported offending up to age 38 years.