I deliberately hedged each defendant's possible negligence.

D1 (Defendant 1) might've negligently injured P. P falls to the pavement, and bleeds. D1 panics, and runs away. D1 is a billionaire.

Next, D2 might've negligently injured P too. After perhaps negligently injuring P, D2 drives P to a hospital’s emergency department ("ED"). D2 is bankrupt. D2's net worth is merely $900.

The ED's lone overworked doctor, D3, might've negligently injured P too. 9 hours after being admitted to the ED, P dies.

Discuss merely all parties’ tortious liability. Ignore — do NOT discuss — damages.

D1 shall try to argue that D2 and D3 broke the chain of causation.

D2 shall try to argue that D3 broke the chain of causation. Obviously D1's argument differs from D2's — because D1 antedated 2 potential intervening acts, but D2 antedated merely 1 potential intervening act.

  1. But wouldn't D1's argument that D3 broke the chain of causation, be the exact same as D2's argument that D3 broke the chain of causation? If not, why not?

  2. In other words, imagine that D1 wrote his Statement of Defence before D2. After deleting all of D1's paragraphs on D3 and changing D1 to D2, can't D2 just copy and paste D1's Statement of Defence?


1 Answer 1


Causation flows forwards in time

Therefore, D1 can argue it was broken by D2 or D3 and D2 can argue it was broken by D3; all other combinations can’t break causation.

What constitutes breaking causation or novus actus interveniens?

Australian Courts have consistently held that to establish a novus actus interveniens capable of severing the chain of causation, the original tortfeasor must establish, on the balance of probabilities, that the subsequent treatment was “grossly negligent”, and therefore not a reasonably foreseeable consequence of the original injury. A mere error or lapse of judgment will not possess enough “causal potency” to amount to an intervening act capable of breaking the chain of causation.

Australian authorities suggest that medical treatment which is unforeseeable is treatment that is “inexcusably bad”, “completely outside the bounds of what any other reputable medical practitioner might prescribe”, or “so obviously unnecessary or improper that it is in the nature of a gratuitous aggravation of the injury” or “extravagant from the point of view of medical practice or routine.” For your example, D2 did not break causation - further injury during transport is not unforeseeable. D3 did break causation - forgetting a patient for 9 hours is “inexcusably bad”.

In terms of liability:

D1 might be liable. However, the “accident” must amount to negligence. If D1 did not owe a duty of care or complied with that duty and the injury was due to pure accident, then they are not liable. The breaking of the chain by D3 means they are only liable for the injuries sustained before then. However, many jurisdictions impose a duty to render aid on a person that caused an accident even if they were not negligent in doing so. Whether D1 leaving the scene creates liability or is merely criminal depends on the specifics of such a law.

D2 probably isn’t liable. In the circumstances, dropping P is likely to be considered a pure accident. In any event, D2 is probably protected by Good Samaritan laws.

D3 is liable, unless P’s injuries were already fatal. That is, there was no possible medical intervention that could be done that would change the fatal outcome.

  • 1
    Sorry, but this does not answer my question. I have numbered them 1 and 2 now. Please carefully reread them. I am hankering to know if D2 and D3's arguments differ, or are the same, on whether D1 broke the chain of causation. I am not seeking an answer on these parties' tortious liability.
    – user42021
    Aug 8, 2022 at 0:17
  • 1
    And why are you citing Australian law, when I tagged England as the jurisdiction and English tort law exists for novus actus interveniens? A first class answer would cite English law.
    – user42021
    Aug 8, 2022 at 0:20
  • 1
    @user This is an answer to the question - paragraph 1 explicitly deals why D2 cannot invoke novus actus interveniens against D1 and D3 cannot against anyone. What do you not understand about it? As for Australian case law a) answers are explicitly not restricted to only the jurisdiction asked about, and b) Australian & English law do not differ materially here.
    – Dale M
    Aug 8, 2022 at 6:55
  • I think the asker got the order wrong (in reverse) but the essence of their question might be: whichever way causation flows, does each defendant's defence differ much or are they mostly identical? I think if you were to reassign the defendant's numbers by swapping D1 and D3 then the question might more directly and accurately ask what the OP wants to know? Aug 8, 2022 at 7:47
  • @DaleM Sorry for my typo. No competent lawyer would cite MERELY Australian law for an English tort case involving novus actus interveniens. This is unprofessional, to say the least.
    – user42021
    Aug 9, 2022 at 0:13

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