A more thorough explanation:

An Allen charge is a set of instructions given to a hung jury to encourage them to reach a unanimous verdict. It is also known as a dynamite, nitroglycerin, shotgun, or third-degree charge. The name "Allen" charge comes from the case Allen v. United States (1896) where the Supreme Court ruled that these types of jury instructions were allowed in Federal courts.

Here is an example of a model Allen charge from the Ninth Circuit:

"Members of the jury, you have reported that you have been unable to reach a unanimous verdict in this case. I have decided to suggest a few additional thoughts to you.

As jurors, you have a duty to discuss the case with one another and to deliberate in an effort to reach a unanimous verdict if each of you can do so without violating your individual judgment and conscience. Each of you must decide the case for yourself, but only after you consider the evidence impartially with your fellow jurors. During your deliberations, you should not hesitate to reexamine your own views and change your opinion if you become persuaded that it is wrong. You should not, however, change an honest belief as to the weight or effect of the evidence solely because of the opinions of your fellow jurors or for the mere purpose of returning a verdict.

I also remind you that in your deliberations you are to consider the instructions that I have given you as a whole. You should not single out any part of any instruction, including this one, and ignore others. They are all equally important.

What I have just said is not meant to rush you or pressure you into agreeing on a verdict. Take as much time as you need to discuss things. There is no hurry.

I ask that you now return to the jury room and continue your deliberations with these additional comments in mind."

Allen charges are controversial because some people believe that they put too much pressure on jurors to change their opinions and agree with the majority. Some states do not allow Allen charges, but Federal courts may use them.

The example of the Allen charge given above shows how the judge encourages the jurors to continue deliberating and to consider the evidence impartially. The judge also reminds the jurors that they should not change their opinion just to agree with the majority, but only if they are persuaded that their opinion is wrong. The judge also emphasizes that the jurors should take as much time as they need to discuss the case and that there is no hurry to reach a verdict.