After all of the evidence and arguments have been presented in a criminal trial, the judge officially hands the case over to a jury for final deliberations. The hope is that all twelve original jurors will be able to reach a unanimous decision and render a verdict. But occasionally a jury may become so divided that a unanimous decision simply cannot be formed. The jury foreman may communicate this impasse through a note to the presiding judge. In order to avoid declaring a mistrial or hung jury, the judge may deliver what is known as the Allen charge, or dynamite charge.
The Allen charge dates back to the case of Allen Vs. United States in 1896. The courts ruled that a judge did have the right to strongly encourage deadlocked jurors to continue deliberations until a verdict is reached. Today, there are a number of variations on the original charge text approved in 1896. Some of these modifications have been declared unconstitutional or prejudicial by appellate courts, so individual judges tend to use their own approved Allen charge. A judge cannot force or coerce a jury into reaching a verdict by mentioning the expenses of the trial, for example.
Because of its strong wording, courts have held that an Allen charge can only be delivered once during the deliberation phase. The judge can use a less stringent form of this charge during his first instructions to the jury, however. Essentially, an Allen charge acknowledges that the jury has become deadlocked or otherwise unable to reach a unanimous decision. The judge reminds the jury of the importance of the trial and how much time and effort has already been expended. Neither the prosecution or defense would want another trial, since the new jury would still hear the same evidence.
The Allen charge also reminds jurors that strongly held beliefs are not the same as careful consideration of the evidence. If the majority of the jurors agree on conviction, those in the minority should ask themselves why their opinions have not swayed the other jurors. If the majority vote for acquittal, then hold-outs for conviction may need to consider reasonable doubt. A modified Allen charge may also use flattering language about the jurors' dedication to duty and their ability to remain open-minded. The ultimate goal of an Allen or dynamite charge is to reinvigorate the jury and discourage lengthy but fruitless deliberations.