PQ (Causation)

Question 1

How do you determine factual causation?

Answer 1

C must establish that D was the factual cause of her loss - using the ‘but for’ test: But for D’s breach, would C have suffered the loss?

[Barnett] - C died of poisoning which could not be removed by Doctor’s treatment

Question 2

How do you determine legal causation?

Answer 2

1. Wilsher v Essex - Burden of proof on the C to prove on balance of probabilities (>50%) that C would not have suffered the loss but for D’s breach

Facts: excessive oxygen supply given by D is one of the 6 causes for baby to go blind. Held that D is not liable on the balance of probabilities.

2. Holtby v Brigham & Cowan - But for causation will allocate liability proportionate to what fulfills the but for test

HELD that D liable only for 75% of injuries as but for D’s act, C would have developed asbestos but it would be 75% less severe.

Question 3

When is causation not established?

Answer 3

When there is a loss of chance. Loss of chance is not a recoverable head of damage in medical negligence claims

Hotson - C had hip fracture and wrong diagnosis led to permanent disability. HELD that D was not liable because C could not establish on balance of probabilities that hospital’s negligence caused harm and could not recover the lost 25% chance of avoiding condition

Gregg v Scott : Wrong diagnosis of lump led to a delay in treatment resulting in cancer spreading. Reduced disease free recovery. HELD Loss of chance claim could not suffice as right diagnosis did not guarantee disease free recovery.

underlying principle: impossible to tell if Doctor had made condition worse

Question 4

What happens when D’s action made C’s injury worse but we don’t know by how much? (Cumulative injury)

Answer 4

Case of a material contribution to physical injury

• If C can prove that D materially contributed to the disease, D is liable [Bonnington Castings]

Note: Injury must be divisible for Bonnington to apply (must be clear that the breach made the injury worse)

Question 5

What happens if it is unknown if cumulative injury D’s actions might have made C’s injury worse, but we don’t know whether they did.

Answer 5

Fairchild: exposure to asbestos causes mesothelioma but it is unknown if it is a cumulative (where the exposure over time made it worse) or single trigger disease.

Held D was liable for materially contributing to an increase in risk and C picked one D to pay 100% of losses

Compensation Act 2006 s3 (apply only for mesothelioma cases) - employers are jointly and severally liable (fully liable) to employees who contracted mesothelioma.

Note: overruled the rule in Barker for mesothelioma cases

Sienkiewicz: D’s workplace exposure increased chance of contracting mesothelioma by 18%

Held that Fairchild applied and D liable for full extent of C’s losses
- Any employer who has negligently exposed claimant to asbestos will be liable in full for C’s losses regardless of level of contribution to risk

(Fairchild exception only applicable to Mesothelioma cases)

Question 6

What is the law for non-mesothelioma cases?

Answer 6

Barker
Facts: exposed to asbestos because of his own-doing

HELD: employers are severally liable in proportion to more of exposure for which they are responsible

Question 7

What is the checklist for Fairchild to apply?

Answer 7

1) Multiple sources of risk
2) Rock of uncertainty (cumulative or single trigger?)
3) Single agent for harm [e.g. asbestos]

If not mesothelioma, apply Barker