R v. Pittwood  TLR 37
The accused was employed by a railway company with a duty to operate the gate at a level crossing. This was meant to prevent accidents from happening and causing harm to others. The accused had opened the gate for a cart to pass, but failed to close it and went on his lunch break. In his absence, a man passed the gate with his horse, and both were killed by a moving train.
Whether or not a contractual duty to act can translate into a criminal duty to act.
By virtue of his contract, the accused was under a duty to act to prevent harm to others in the present case.
The court held that his failure to perform the duty of closing the gate, an omission, could constitute the actus reus for murder. Thus, the accused, by failing to close the level gate, an omission, was deemed to have caused harm by omission because he was under a contractual obligation to act to prevent such harm. He was found guilty of gross negligence manslaughter.