Primary tabs

Negligence is a failure to behave with the level of care that someone of ordinary prudence would have exercised under the same circumstances.  The behavior usually consists of actions, but can also consist of omissions when there is some duty to act (e.g., a duty to help victims of one's previous conduct). 


Primary factors to consider in ascertaining whether the person's conduct lacks reasonable care are the foreseeable likelihood that the person's conduct will result in harm, the foreseeable severity of any harm that may ensue, and the burden of precautions to eliminate or reduce the risk of harm. See Restatement (Third) of Torts: Liability for Physical Harm § 3 (P.F.D. No. 1, 2005).  Negligent conduct may consist of either an act, or an omission to act when there is a duty to do so.  See Restatement (Second) of Torts § 282 (1965).

Four elements are required to establish a prima facie case of negligence: 

  1. the existence of a legal duty that the defendant owed to the plaintiff
  2. defendant's breach of that duty
  3. plaintiff's sufferance of an injury
  4. proof that defendant's breach caused the injury (typically defined through proximate cause)

Determining a Breach

When determining how whether the defendant has breached a duty, courts will usually use the Hand Formula (created by Judge Learned Hand in United States v. Carroll Towing): 
  • If B < PL, then there will be negligence liability for the party with the burden of taking precautions
    • B=burden of taking precautions
    • P=probability of loss
    • L=gravity of loss (gravity of the personal loss, not social loss)
If the burden of taking such precautions is less than the probability of injury multiplied by the gravity of any resulting injury, then the party with the burden of taking precautions will have some amount of liability

Determining Whether There Was A Duty To Act

Typically, if the defendant had a duty to act, did not act (resulting in a breach), and that breach caused an injury, then the defendant's actions will be classified as misfeasance. There are several ways to determine whether the defendant had a duty to act (note: this is NOT an exhaustive list):

  1. The defendant engaged in the creation of the risk which resulted in the plaintiff's harm
  2. Voluntary undertaking: The defendant volunteered to protect the plaintiff from harm 
  3. Knowledge: The defendant knows/should know that his conduct will harm the plaintiff
  4. Business/voluntary relationships: ex: business owner and customer; innkeeper and guest; land possessor who opens her land to the public; person who voluntarily takes custody of another person

Determining Whether There Was An Injury

Typically in order to meet the injury element of the prima facie case, the injury must be one of two things:

  1. bodily harm
  2. harm to property (can be personal property or real property)

Pure economic loss will usually not meet the injury requirement. Sometimes emotional distress/harm may meet the bodily harm requirement (even if there is no accompanying physical harm). 

See also: