Doctrine of last clear chance
From Legal Wiki
The negligence of a claimant does not preclude a recovery for the negligence of defendant where it appears that the latter, by exercising reasonable care and prudence, might have avoided injurious consequences to claimant notwithstanding his negligence. As the doctrine usually is stated, a person who has the last clear chance or opportunity of avoiding an accident, notwithstanding the negligent acts of his opponent or the negligence of a third person which is imputed to his opponent, is considered in law solely responsible for the consequences of the accident.
In essence, the doctrine of last clear chance is to the effect that where both parties are negligent but the negligent act of one is appreciably later in point of time than that of the other, or where it is impossible to determine whose fault or negligence brought about the occurrence of the incident, the one who had the last clear opportunity to avoid the impending harm but failed to do so, is chargeable with the consequences arising therefrom. Stated differently, the rule is that the antecedent negligence of a person does not preclude recovery of damages caused by the supervening negligence of the latter, who had the last fair chance to prevent the impending harm by the exercise of due diligence.