DEFINITION of Omission

Omission is a failure to act that causes harm. Omission (to act) or failure to do so is only criminal in three situations:

  • When there is a statute that creates a legal duty to act;
  • When there is a contract that creates a legal duty to act;
  • When there is a special relationship between the parties that creates a legal duty to act.

Prosecution for a failure to act is relatively rare, since individuals cannot be compelled to put themselves in harm’s way and in a situation where there are multiple bystanders, it becomes impossible to assign blame for inaction to a specific person. However, omission to act becomes a crime if three elements can be established – that there was a duty of care, that this duty was breached, and that there is a direct connection between the breach of duty and the harm suffered. A breach of duty would not occur if the conduct was justified or if the duty was impossible.


Examples of a statutory duty to act are the duty of social workers to report child abuse, or the duty of health-care staff to report gunshot wounds. In many U.S. states, “Good Samaritan” statutes create a duty to help those involved in an accident or emergency. While these statutes generally contain provisions that shield a person from liability when providing assistance, a landmark case in California illustrated the limits of such liability protection.

That case resulted from an accident in the Los Angeles area in October 2004, when a woman pulled her injured friend from a wrecked car. However, the rescuer was sued by the friend on the grounds that she had pulled her roughly – “like a rag doll” – from the car, contributing to spinal injuries that left her permanently paralyzed. California’s Good Samaritan law stated then that “no person who in good faith, and not for compensation, renders emergency care at the scene of an emergency shall be liable for any civil damages resulting from any act or omission.” However, two California courts interpreted “emergency care” as “medical care,” which can only be provided by trained medical personnel who are legally protected. The statute has since been revised to cover emergency medical or nonmedical care at the scene of an emergency.

Examples of a Contractual Duty to Act

A physician’s duty to help a patient is an example of a contractual duty to act. A leading case on this duty is R v Pittwood (1902). In this case, a railway crossing gate-keeper lifted the gate to allow a cart to pass but then failed to put the gate down when he left for lunch. Subsequently, a train collided with a horse and cart killing the train driver. The gate-keeper was convicted of manslaughter as it was his contractual duty to close the gate.

Special relationships such as that between parent-child, or between spouses, also form the basis of a legal duty to act, especially when one individual depends on the other. Thus, a parent is obligated by law to provide food, shelter, and medical care to his or her child, since the child is wholly dependent on the parents for the basic necessities of life.