Allen v. United States (1896) was a United States Supreme Court case that first approved of a judge giving an instruction to a deadlocked jury for them to reconsider their votes in order to prevent a hung jury. It specifically is used when an overwhelming majority of the jury is in agreement and there are only one or two dissenters. While it isn't requiring the dissenting jurors to change their vote, it is encouraging them to be sure that their vote is based on the facts of the case and the law and not instead on their own personal feelings or beliefs. It also encourages them to consider that if their arguments are not convincing to the majority of their fellow jurors that they be absolutely sure that they truly are convinced, beyond a reasonable doubt, of their vote.
After that case such an instruction became known as an Allen charge and was used to prevent a hung jury due to a small minority disagreeing with the majority. Because it is used to dislodge jurors from entrenched positions, the Allen charge is sometimes referred to as the "dynamite charge" or the "hammer charge." Since the ruling was made in the federal Supreme Court, state courts are not required to abide by the ruling. In fact 23 states in the US have laws that prohibit the use of a Allen charge.
After that case such an instruction became known as an Allen charge and was used to prevent a hung jury due to a small minority disagreeing with the majority. Because it is used to dislodge jurors from entrenched positions, the Allen charge is sometimes referred to as the "dynamite charge" or the "hammer charge." Since the ruling was made in the federal Supreme Court, state courts are not required to abide by the ruling. In fact 23 states in the US have laws that prohibit the use of a Allen charge.