What does research comparing criminality of identical twins and fraternal twins tend to find?

Research comparing the criminality of identical twins and fraternal twins typically finds greater concordance among identical twins. This is largely because identical twins share 100% of their genes, while fraternal twins share approximately 50% of their genes. The higher concordance in criminal behavior observed among identical twins suggests a significant genetic component influencing criminality.

These findings indicate that genetics plays a crucial role in predisposition to criminal behavior, as identical twins raised in the same environment tend to have more similar rates of criminality compared to fraternal twins. Such studies provide key insights into understanding the nature versus nurture debate in criminology, emphasizing how hereditary factors can contribute to an individual's propensity for engaging in criminal activities.

Fraternal twins, while still genetically related, do not show the same level of concordance as identical twins due to their differing genetic makeup. This distinction underscores the influence of genetics on behavioral outcomes, making the observed trends in identical twins an important area of focus in criminological research.