Mistake of Fact

An error that is not caused by the neglect of a legal duty on the part of the person committing the error but rather consists of an unconscious ignorance of a past or present material event or circumstance or a belief in the present existence of a material event that does not exist or a belief in the past existence of a material event that did not exist.

Mistake of fact can be a factor in reducing or eliminating civil liability or criminal culpability. A mistake of fact is of little consequence unless it is born of unconscious ignorance or forgetfulness. A person cannot escape civil or criminal liability for intentional mistakes.

In contract law a mistake of fact may be raised as a defense by a party seeking to avoid liability under the contract. Also, a mistake of fact can be used affirmatively to cancel, rescind, or reform a contract. A mistake of fact can affect a contract only if the mistaken fact was material, or important, to the agreement.

For example, assume that a bookseller has agreed to sell a copy of a Virginia Woolf novel that was signed by the late author. Assume further that the buyer is only interested in buying the book because it contains Woolf's signature. The seller knows this, and with an authentic signature the book fetches a very high price. If it is later discovered that the signature was actually forged decades earlier and neither the seller nor the buyer knew of the forgery, this would be a mistake of fact material to the deal, and the buyer would have the right to return the book and get her money back. This example illustrates a mutual mistake, or a material fact that is mistaken by both parties. In such a case, the party who is adversely affected by the mistake has the right to cancel or rescind the contract.

In the event of a unilateral mistake, only one party to the agreement is mistaken about a material fact. In such a case, the party adversely affected by the mistake will not be able to void the contract unless the other party knew or should have known of the mistake, or unless the other party had a duty to disclose the mistaken fact. For example, assume that a person owns an expensive sports car that is in perfect condition. Assume further that a neighbor asks the owner if he will sell the car, and the owner responds, "I will sell this car for thirty bills." If the neighbor returns with $30, no contract is formed because the neighbor mistakenly thought that the owner meant $30 when actually the owner was using slang for $30,000. Further, the neighbor should have known that an expensive sports car would not be sold for $30.

If a party to a contract assumes the risk that a material fact may be different than expected, that party will not be able to recover any losses when the fact turns out to be different. For example, assume that a farmer sells a horse to a buyer who wants to use the horse for polo games. Neither the farmer nor the buyer knows whether the horse will be suitable for polo, and the farmer makes no guarantees. If the horse proves unsuitable, the buyer will not be able to rescind the deal because the farmer made no warranties as to the horse's suitability for polo. To avoid such a result, parties to a contract may agree, as part of the deal, to cancel or rescind the contract if a certain fact related to the contract later proves unacceptable to one of the parties.

If a contract can be reformed, a court may not allow a party to rescind a contract on account of mistake of fact. The court reforms a contract to reflect the true intent of the parties. For example, assume that a footwear retailer offers to buy 100 mukluks from a mukluk manufacturer for $10 a pair. Assume further that the retailer mistakenly orders 100 mukluks for $100 a pair. If the mukluk manufacturer delivers 100 mukluks and later demands $100 for each pair, the retailer can ask a court to reform the contract to reflect a price of $10 a pair. This action generally occurs when the mistake makes the agreement UNCONSCIONABLE. If, for example, the retailer had offered to pay $101 a pair and the retailer later discovered that the standard price was $100, the retailer would likely be stuck with the contract.

A mistake involving the use of force in the defense of property can give rise to civil liability. Generally, if a person has a privilege to enter onto property, a landowner or tenant has no right to use force to keep the intruder off the property. If, however, the intruder causes a reasonable, mistaken belief that the property must be defended, a landowner or tenant may have the right to use force to repel the intruder. For example, if an electricity meter reader arrives to read a meter at night wearing dark clothing and a ski mask, a resident on the property may not be liable for a reasonable use of force necessary to expel the intruder. The meter reader can be considered to have caused the mistaken belief on the part of the resident that the property was being invaded by someone with no privilege to enter.

In CRIMINAL LAW an honest and reasonable mistake of fact can eliminate the mens rea element of criminal responsibility. Mens rea is Latin for "guilty mind," and, along with an act, a guilty mind, or a criminal intent, is required before a person can be held criminally responsible for most crimes. For example, assume that a person who buys stolen goods honestly and reasonably believed that the goods actually belonged to the seller. This would negate the criminal intent necessary to be convicted of receiving stolen goods, and the buyer would not be held criminally liable.

If a mistake of fact in a criminal case does not negate mens rea, it may reduce it. For example, if a person honestly and reasonably, but mistakenly, believes that DEADLY FORCE is necessary to preserve her own life, she may not be found guilty of murder if a death results from the deadly force. The mistake reduced the mens rea necessary to be convicted of murder. That is, the person did not have the SPECIFIC INTENT to kill without justification or excuse. She may be found guilty of MANSLAUGHTER, a HOMICIDE less serious than murder, if her actions were unreasonable. She may even be found not guilty of any homicide if the judge or jury finds that she was not reckless or negligent in the killing. This is a QUESTION OF FACT to be determined by the judge or jury sitting on the case.

In some criminal and civil cases, no mens rea is required for liability. Such cases involve STRICT LIABILITY crimes. STATUTORY RAPE is an example of a strict liability crime. It does not matter whether the defendant knew that the victim was too young to have sexual relations or whether the defendant intended to have sex with a minor. In such a case, a mistake of fact is no defense. Strict liability crimes are generally those that endanger the public WELFARE, such as toxic waste dumping and the sale of alcohol to minors.