How does a jury work?

A jury trial is a trial in which the jury, not the judge, decides whether the facts of the case have been proven or not.  A jury is a group of people, usually chosen at random among adults in the community. During the trial, the jury listens to, sees, and reads all of the evidence presented.  Most juries contain six to 12 people, depending on the size of the case and whether it is a civil or criminal issue.

The purpose  of a trial is to address a dispute between two or more parties.  The issues in each court case fall into one of two categories: questions of fact and questions of law.

Questions of fact are questions that deal with what actually happened in the case.  For instance, suppose the plaintiff in a personal injurycasewas walking through a crosswalk one day when the defendant hit her with his car.  The plaintiff sues the defendant, claiming that the light was red and so the defendant should have stopped instead of continuing to drive through the intersection and thus hitting the plaintiff.  The defendant, however, argues that the light in his direction was green, and so he did not have to stop and the plaintiff should have waited to cross, since she was facing the “don’t walk” sign.

What color the light was when the accident occurred is a question of fact.  If it was red, it supports the plaintiff’s case; if it was green, it supports the defendant’s case.  Questions of fact like these are the jury’s responsibility.

Questions of law, on the other hand, are not about the facts in a particular case, but about how the law should apply in the case.   For example, in the case described above, the color of the traffic light is a question of fact.  However, the question of whether the defendant was negligent by driving through the light is a question of law, because it asks whether the law of negligence applies to the defendant’s actions.  Questions of law are generally decided by the judge.

A jury trial may or may not be a constitutional right, depending on the type of case and the law in the state where it is heard.  The U.S. Constitution gives parties in federal court the right to a jury trial if the amount in dispute is over $20.00 – a large sum in 1789, but a small one today.  This rule does not apply to state courts, however, where the right to a civil jury trial depends on the laws of that particular state.  Most defendants in criminal cases, on the other hand, have a right to have their case heard by a jury.

Because of the presence of the jury, a jury trial contains some elements that a bench trial does not.  The most prominent of these is voir dire, which is the process by which the attorneys for each side pick jurors.  During voir dire, attorneys ask the jurors questions to learn a little about them and get a sense of how well they understand issues like the one in the case.  For instance, an attorney for a plaintiff injured by a defective drug might ask the jurors whether they have taken the same medication, whether they know someone who has, and whether they have ever been injured by a defective drug before.

Both the prosecution or plaintiff and the defense will ask potential jurors about their opinions on matters relevant to the trial. Lawyers are permitted to dismiss jurors for several reasons:

  • Bias against their side of the case
  • Prior knowledge of the case
  • Previous experience with similar charges
  • Previous jury experience

Lawyers may also use a limited number of “peremptory strikes,” in which they can dismiss a prospective juror without giving a reason.

After each round of questioning, the attorneys may “strike,” or remove, at least one juror.  Striking a juror “for cause” means removing that particular juror because some legal rule or regulation prohibits them from hearing the case.  For instance, an attorney might strike a juror for cause if she found out that the juror was on parole and her state’s law prohibits parolees from serving on juries.  Attorneys may also strike a juror for purely strategic reasons, without explaining why.  These strikes are known as “peremptory strikes,” and attorneys in most states are limited to only a few strikes per side. The US Supreme Court has ruled that lawyers may not use peremptory strikes based solely on a juror’s race, gender, or ethnicity.

Once voir dire is complete, the jury hears the case.  Then, the jury remains in the courtroom while the judge reads the jury instructions.  Jury instructions are plain-language explanations of the law that applies to the case.  These instructions are intended to prepare the jury to discuss the evidence and come to a conclusion about whether or not the plaintiff proved her case.  These discussions take place in a separate jury room and are considered private, though jurors in some states may discuss them after the verdict has been read.

Jurors are not permitted to read, watch, or listen to outside news or discussion about the trial, such as newspaper, website, or TV coverage. They may not conduct their own research into the circumstances of the case or into the law.

In most criminal cases, the jury’s decision must be unanimous; Oregon and Louisiana are the only states where non-unanimous criminal verdicts are allowed, and even then there are some restrictions on how they may be used.

If the jurors cannot agree on a verdict, the jury is considered “hung” and the case is declared a mistrial. Mistrial cases may be tried again later with a different jury, or the prosecutor may decide not to bring the case again, in which case the charges are dropped and the defendant goes free.


Republished with permission under license from the Rottenstein Law Group LLC, some edits have been made to the original article.

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