Proxy murder
An example of this would be an assassin killing for money.  Another example would be a person that convinces someone that loves them to kill another person for them. Another example was in prisons where criminals in prison would act as the executioner for people sentenced to death. Lady Betty (1750—1807) was a famous hangwoman and prisoner in the Roscommon Gaol. The Nazis used proxy killings in World War II when they got prisoners to shoot Jewish prisoners instead of doing it themselves. The prisoners were told if they did not do it they would be shot as well.