Issues with Lombroso's research is that it has been implicated with scientifically validating racism.
This is because Lombroso highlights features in his atavistic form such as dark skin and curly hair as features of criminality.
This draws attention to individuals of afro-carribbean descent and places them under scrutiny and stigmatises them as criminals.
It leads to the pathologising of minority groups which in turn could have led to eugenics.