From: American Bar Association
After receiving the instructions and hearing the final arguments, the jury retires to the jury room to begin deliberating. In most states the first order of business is to elect one of the jurors as the foreperson or presiding juror. This person’s role is to preside over discussions and votes of the jurors, and often to deliver the verdict. The bailiff’s job is to ensure that no one communicates with the jury during deliberations.
In some states, the jury may take the exhibits introduced into the record and the judge’s instructions to the jury room. Sometimes the jury will have a question about the evidence or the judge’s instructions. If this happens, the jury will give a note to the bailiff to take to the judge. The judge may respond to the note, or may call the jury back into the courtroom for further instructions or to have portions of the transcript read to them. Of course, any communication between the judge and jury should be in the presence of lawyers for each side or with their knowledge.
Usually the court provides the jury with written forms of all possible verdicts, so that when a decision is reached, the jury has only to choose the proper verdict form. In most instances, the verdict in a criminal case must be unanimous. In some states a less than unanimous decision is permitted in civil cases. All federal cases require a unanimous decision.
If the jury cannot come to a decision by the end of the day, the jurors may be sequestered, or housed in a hotel and secluded from all contact with other people, newspapers and news reports. In most cases, though, the jury will be allowed to go home at night. The judge will instruct jurors not to read or view reports of the case in the news. Nor should they consider or discuss the case while outside of the jury room.
If the jurors cannot agree on a verdict, a hung jury results, leading to a mistrial. The case is not decided, and it may be tried again at a later date before a new jury.