Legal Maxim: Novus Actus Interveniens

Introduction 

The term Novus Actus Interveniens simply means a new intervening act or event that breaks the chain of causation i.e. it breaks the causal link between an original wrongful act and its consequences. It is a Latin legal term; in the context of Law of Torts, Novus Actus Interveniens can be used as a defense by the Defendant for the reason that they should not be made liable for subsequent events due to an independent, intervening act. It must be firstly determined whether such act qualifies as Novus Actus Interveniens, that affects the chain of causation based on its foreseeability and direct connection to the original act.

Meaning 

Novus Actus Interveniens is a Latin term that can be translated as "new intervening act."

• It is one of the most significant doctrines in the Law of Torts and is generally applied to the issue of negligence.
• It is defined as an independent intervening act which occurs after the wrongful act of the defendant, thereby breaking the chain of causation established between the defendant's act and harm caused to the plaintiff.
• This legal principle, therefore, is critical to determining liability since it exculpates the defendant from the potential consequences of the actions if, indeed, an intervening act is considered unforeseeable and serious enough to break the causal chain.

The Tests of foreseeability and direct damage are essential to determine if an event qualifies as a Novus Actus Interveniens. These tests help assess if the causal link between the defendant’s actions and the plaintiff's harm has been severed.

1. Test of Foreseeability: The test considers whether the intervening act could have been foreseen by the defendant at the time of the wrongful act. If the intervening event was foreseeable, it means the defendant had knowledge of the situation. However, causation is not interrupted by an intervening act if it leaves the defendant still liable for the injury. Conversely, the act may qualify as Novus Actus Interveniens if it was not reasonably foreseeable which can result in exoneration of the defendant from liability for injuries that arose after the event occurred.

2. Test of Direct Damage: This test examines whether the injury sustained by the plaintiff directly results from the primary wrongful act or from the intervening event. In the case where the injury was caused directly by the defendant, even in the presence of an intervening event, liability may still rest with the defendant. However, if the loss mainly stems from the intermediate wrong and is not caused by the original wrongful act, the causal chain is broken and the defendant cannot be held responsible for the damages thus suffered[1].

Novus Actus Interveniens as a Defense in Law of Torts

The expression Novus Actus Interveniens can be used as a defense in Law of Torts wherein the defendant can use it to argue that an independent act intervened after their original wrongful act, effectively breaking the chain of causation between his actions and the plaintiff's harm. Thus, here's how this defense may be constructed:

• The Initial Act of Negligence: The defendant must first admit to having committed a breach of duty or negligence, which at some level of injury is caused to the plaintiff. This marks the starting point of analysis in the determination of causation.
• The Interfering Act: The defendant must also be able to identify some subsequent interfering event or action that occurs after the defendant has performed his primary act. The interference shall be such that it is neither caused nor foreseen as a natural consequence of the defendant's act. Few examples include: actions of the plaintiff, which exacerbated the injuries sustained; third-party acts on the part of another; or forces of nature. In Barnett v. Chelsea & Kensington Hospital Management Committee[2], a man went to the hospital suffering from poisoning, but was not treated appropriately due to the negligence of the hospital, resulting in his death. The court held that even if he had been properly treated, he would still have died because of the effect of the poison. The court ruled that the death was not caused due to the hospital’s negligence, as the intervening act-the poison was the direct cause of harm.
• Showing Foreseeability: The act of the defendant should prove that the intervening act was not reasonably foreseeable at the time of the defendant's initial wrongful act. If such an event had been reasonably foreseeable, then that plea would not be allowed. This is where the test of foreseeability comes in, as it decides whether the defendant should have provided for that possibility and accounted for its arrival. In Haber v. Walker[3], the court established critical principles regarding Novus Actus Interveniens. It was held that for an act to be treated as a Novus Actus, it has to be an intervening event which ought not to have been foreseeable at the time of the initial wrong. This case is often cited to illustrate tests of foreseeability and direct damage regarding whether an intervening act breaks the chain of causation.
• Demonstrating the Break in Causation: This requires that the intervening act be significant enough in nature to break the causal chain between the defendant’s actions and the plaintiff’s injuries. This is established when it can be shown that the loss which plaintiff claims recovery for is primarily caused by the intervening act rather than the defendant's initial conduct. If the court determines that the intervening act is actually the cause of the injury, then the defendant can be acquitted of the liability.
• Supporting Evidence: The defendant should provide some evidence for his or her claims about the intervening act, such as witness testimonies, expert opinions, or documentations demonstrating how the intervening act occurred and how it could have affected the plaintiff's injuries.

Situations that Qualify as Novus Actus Interveniens 

Here are mentioned few examples of how some situations may qualify as Novus Actus Interveniens, or an independent intervening act, which breaks the chain of causation in cases of Law of Torts:

1. Medical Negligence: If a plaintiff suffers an injury due to the negligence of a defendant (for example: car accident). The plaintiff subsequently receives improper medical treatment that exacerbates his injuries. Provided that the medical malpractice is unforeseeable and significantly worsened the plaintiff's condition, this would qualify as a Novus Actus Interveniens, this breaks the chain of causation to the original accident. In MEC Health, Eastern Cape v. Mkhitha[4], the negligent medical treatment that the plaintiff subsequently received was not considered a natural consequence of the initial accident. The court held that medical negligence constituted an independent intervening act, which altered the cause of liability of the original wrongdoer and, as a matter of law, qualified as Novus Actus Interveniens applicable in cases of medical negligence.
2. Criminal Acts by Third Parties: If a person is injured by his roommate due to safety negligence on the part of the bar owner during a fracas at a bar, and later, after the initial injury, a third party (who was not involved in the fracas) intentionally assaults the plaintiff, causing further harm, this may be considered a Novus Actus Interveniens. The third party’s act is an independent and unforeseeable event that caused additional injuries to the plaintiff. In Weld Bundell v. Stephens[5], the actions of the third party-specifically the manager who discovered and relayed the libel-were independent and voluntary actions that broke the chain of causation. Since the actions of the manager were beyond the control of the appellant, the appellant could only recover nominal damages, as Novus Actus Interveniens applies to this situation.
3. Natural Disasters: If a construction company negligently damages a building's foundation, and later a violent earthquake strikes, causing the building to collapse. In this situation if the court rules that the earthquake is an unforeseeable act that directly caused the damage. In such a case, the earthquake could break the chain of causation between the construction company’s negligence and the damage caused by the earthquake.
4. Plaintiff's Own Actions: If a plaintiff suffers a minor injury due to the negligence of a defendant (for example, falling on a slippery floor), and later the plaintiff voluntarily decides to jump from a roof resulting in more severe injury, this would breaks the causal chain between the defendant's initial negligence and the plaintiff's more serious condition.
5. Acts of God: If a driver negligently causes a minor accident, and shortly afterwards, a severe storm hits, knocking down a tree on the vehicle and causing serious damage. The storm could be considered as Novus Actus Interveniens, thereby breaking the causal connection with the driver's primary act of negligence.

Conclusion

In practice, Novus Actus Interveniens is regularly applied in areas like medical negligence, personal injury, and third-party actions. The application of the doctrine highlights the importance of considering individual circumstances to assess the extent of liability in each case. Ultimately, Novus Actus Interveniens serves as an important mechanism in Law of Torts where it plays a key role in determining whether a defendant should be held liable for harm caused by an event resulting from an independent and unforeseeable act.

[1]. R.K. Bangia’s The Law Of Torts (Revised by Dr. Narender Kumar).

[2]. [1968] 2 WLR 422.

[3]. [1963] VR 339.

[4]. [2016] ZASCA 176.

[5]. [1920] UKHL 64658 SLR 646.