A jury is considered "deadlocked" when it is unable to reach an unanimous decision. In Tennessee personal injury and wrongful death trials a jury of twelve people sits in judgment of the case and all twelve must agree on all issues. When they fail to do so they are "deadlocked."
A judge faced with a deadlocked jury has two choices. First, the judge can send the jury home, declare a mistrial, and order the parties to another trial. This is an expensive option, both for the parties to the lawsuit and the justice system, because of the money that will be spent on the new trial.
The other option is for the judge to give what is known as a "dynamite" or "Allen" charge. A dynamite or Allen charge is a jury instruction that strongly encourages each juror to reconsider his or her views and work toward compromise. It tells jurors that a new trial will be very costly to the parties and that the jurors should work harder to solve their differences.
Under Tennessee law such a jury instruction can be given in a civil case only if the parties to the case agree to the charge. Otherwise, the mere giving of the charge can result in the case being reversed on appeal.
Many states do not require unanimous jury verdicts in personal injury, wrongful death or other types of civil cases and thus rarely have deadlocked juries. These states usually allow one, two or even three of the twelve jurors to disagree with the remaining jurors and the jury verdict of the super-majority is still valid.