In order to determine the extent to which genetics may play a role in the criminal activity

In order to determine the extent to which genetics may play a role in the criminal activity, psychologists have carried out twin studies. German physiologists, Johannes Lange, have conducted an investigation with a group of thirteen pairs of adult male identical twins. He found out that if one twin had a record of imprisonment, the other pair similarly had been imprisoned in seventy-seven percent of the cases; whereas in a comparable group of seventeen pairs of fraternal twins, when one twin had been imprisoned, the other had a prison record in only twelve percent of the cases. Johannes have proposed a conclusion that criminal behavior among identical twins were greater than fraternal twins.