⇒ Generally, a person will not be liable for simply failing to act. In English law, at least, if you come across a child drowning in a pond and simply leave that child to die you will not be criminally liable.

⇒ However, in some circumstances it may be possible to be criminally liable for an omission where there is a duty to act in a particular way. The following section demonstrates situations where the defendant will be under a duty to act, such that an omission could lead to criminal liability.

⇒ Statutory duty: In some situations there is a statutory duty to act. For example, to provide details of insurance after a traffic accident or to notify DVLA when you sell a vehicle. Failure to do so will lead to criminal liability.

⇒ Duties of law enforcement: Police officers have a duty to assist members of public in danger; if they fail to do so they will be criminally liable. See R v Dytham, for example.

⇒ Contractual duty: If a person owes a contractual duty to act, then a failure to meet this contractual duty may result in criminal liability. See R v Pittwood, for example.

⇒ Assumed duties: People who voluntarily assume responsibility for another’s welfare will be under a duty to care for him or her; failure to do so will result in criminal liability. See, for example, the cases of R v Instan, R v Stone & Dobinson, and R v Gibbins & Proctor.

⇒ Continuing act: This is most easily explained by the case of Fagan v Metropolitan Police Commissioner.

⇒ Creation of the danger: If a person creates a dangerous situation through his own fault, he may be under a duty to take reasonable steps to avert that danger, and may therefore incur criminal liability for failing to do so. See R v Stone & Dobinson, and R v Miller, for example.

⇒ Novel situations: It seems that the list of exceptions is not necessarily a closed list. The courts may be willing to create new circumstances under which there is a duty to act.

⇒ In simple terms, if there is a duty to act the defendant must do what is reasonable. What is reasonable will be decided by the jury in each case.

⇒ For example, if you saw your child drowning in a shallow pool it would be reasonable for you to save him/her. Failure to do so would be a criminal offence. However, if you saw your child drowning in shark infested waters in the high seas, it would be - perhaps - unreasonable to suggest you should save him/her.

⇒ Nevertheless, even where it may be unreasonable to act, it may still be reasonable to seek help.

⇒ It must also be shown that the omission caused the harm. See, for example, R v Dalloway.

⇒ This distinction doesn’t seem difficult, but it can be surprisingly hard. See, for example, R v Speck.

⇒ The leading case in demonstrating how difficult it can be to determine the difference between an act and an omission is Airedale NHS Trust v Bland.

⇒ Similar to omission offences, a person can also be guilty if he/she is found to be in a particular situation. For example, drink driving and possession of drugs are situational offences.

⇒ Situational offences usually involve a voluntary act. For example, possessing drugs would involve either buying or making the drugs and putting them into your bag/pocket.

⇒ It may be the case that someone could be held criminally liable for someone else’s acts.

⇒ For example, vicarious liability means that an employer may be criminally responsible for the acts of their employees.