Beyond a Reasonable Doubt

In the U.S. criminal legal system, a prosecutor bears the burden of proving that the defendant is guilty “beyond a reasonable doubt” of the crime for which he has been accused. This means that the proposition, scenario, or facts presented by the prosecution must be proven to the jury to the extent that there could be no “reasonable doubt” in the mind of a “reasonable person” that the defendant is guilty. If, after all evidence and testimony have been presented, even a small doubt affects any member of the jury’s belief that the defendant is guilty, the burden of proof has not been met. To explore this concept, consider the following beyond a reasonable doubt definition.



  1. A feeling of uncertainty about the truth, the reality of a situation or presented facts, or nature of something
  2. To be uncertain about a thing; to be undecided in a belief or opinion


1175-1225   Old French douter



  1. Acceptable to sound reason or judgment, logical


1250-1300  Middle English resonable

History of the Standard of Reasonable Doubt

The Western standard by which accused people are judged originated in medieval England, which held jurors to a strict religious standard in passing judgment. Prior to the “reasonable doubt” concept, passing judgment on an individual in a criminal trial exposed jury members to the edict that, whoever found another person guilty, was subject to the “vengeance of God upon his family and trade, body and soul, in this world and that to come.”

In response to the difficulty in obtaining a conviction because of the religious fears placed upon jurors, the concept of “reasonable doubt” was introduced to the legal system in the late 18th century.

The Burden of Proof

The burden of proof is a requirement for one party in a trial to provide evidence that shifts the opinion and conclusion away from the opposing party’s position to one’s own position. How convincing the evidence needs to be to accomplish this in a court of law varies according to the type of trial. While the burden of proof necessary to convict a person of a crime is “beyond a reasonable doubt,” a much lower standard of proof is required in civil matters.

  • Preponderance of Evidence – The evidence in a case is convincing that the facts as presented by one party are more likely to be true than not true. In some cases, the standard is held to a greater than 50 percent chance that the facts are true.
  • Clear and Convincing Evidence – While the requirement of clear and convincing evidence there is a high probability that the facts as presented by one party are true. While this seems very similar to the preponderance of evidence requirement, the requirement for clear and convincing evidence is actually a higher standard of proof.
  • Beyond a Reasonable Doubt – The evidence presented by the prosecutor in a criminal trial proves the defendant’s guilt to such a degree that no reasonable doubt could exist in the mind of a rational, reasonable person.

The reason the burden of proof in a criminal trial is so strict is that, while a civil trial may result in the defendant being ordered to make monetary payment, a criminal conviction may result in the defendant being deprived of his freedom, or even in his death.

Reasonable Doubt in Practice

In a 1995 trial that lasted nine months, former football player O.J. Simpson was accused of the brutal murder of his ex-wife, Nichole Brown Simpson, and her friend Ronald Goldman. The prosecution presented both lay and expert witnesses, as well as a mountain of evidence over the course of six months in an attempt to prove to the jury that Simpson committed the murders.

When Simpson’s rock star team of attorneys took over to present his defense, their only goal was to create even a small doubt in the minds of the jurors that Simpson had killed his ex-wife and Goldman. On May 15, 1995, O.J. Simpson, standing in front of the jury box, tried on the bloody leather glove that had been presented as a key piece of evidence by the prosecution, showing his hand could not fit into the glove. This gave rise to attorney Johnny Cochran’s now-famous declaration, “If it doesn’t fit, you must acquit.”

After deliberating less than four days, the jury found O.J. Simpson not guilty on both counts of murder. Although a huge amount of evidence, much of it accompanied by complex explanations, was presented to the sequestered jury, that one act of trying on the glove was perhaps the greatest influence in derailing the entire case. Members of the jury simply could not find that Simpson was guilty beyond a reasonable doubt.

One year later, the families of Nichole Brown Simpson and Ronald Goldman filed a wrongful death civil lawsuit against Simpson. The jury in this civil trial believed the families’ attorney who said, “there’s a killer in this courtroom.” With the lower standard of proof being “a preponderance of the evidence,” the jury found Simpson liable for the deaths and award the families $8.5 million in damages. Simpson was subsequently ordered to turn over, not only his monetary assets, but his 1968 Heisman trophy, a Warhol painting, and his golf clubs.

Related Legal Terms and Issues

  • Preponderance – a superiority in importance, strength, power, or weight.
  • Acquit – to relieve someone from a criminal charge; to declare not guilty
  • Wrongful Death – the death of an individual caused by the willful or negligent actions of another person.