Causation - Material Contribution to Damage Test [Factual Causation]

Test for Material Contribution to Damage

Authority: Bailey & Bonnington

Need to state whether the breach had materially contributed to the damage on a balance of probabilities

Usage of Test: When there are multiple causes and sources and the damage from the cumulative injury cannot be attributed to one particular source (Medical Science cannot establish that the probability of the “but for” test an act of negligence the injury would not have happened but can establish with certainty that the contribution of the damage was more than negligible (Bailey v Ministry of Defence)

If the evidence of the test cannot demonstrates on a balance of probabilities that the injury would have occured as a result of the non- tortious cause or causes in any event the Pf would have failed to establish the tortious cause contributed (Pai Lily)

How to determine whether to use Material Contribution to Risk or Material Contribution to Damage Test

(1) Must first establish that the But for test does not work

(2) Look at whether medical science can certainly and actually materially contributed to the damage (it is not “could have” contributed)

• If scientific evidence can with certainty confirm that the breach actually and certainly contributed, then use Material Contribution to Damage if not resort to Material Contribution to risk.

(3) Material Contribution to Damage can have multiple sources that cause the injury or damage unlike Material Contribution to Risk where there can only be one causal mechanism but there can still be multiple causal agents (ie. tortious action/ non-tortious actions)

Bailey v Ministry of Defence

Held: That the Df was liable based on the material contribution to damage test on a balance of probabilities. Even though the overall weakness was materially contributed by both negligent and non-negligent causes. As the injury was indivisible, the Pf was held fully liable.

Facts: Pf went for gall bladder surgery and developed pancreatitis. She went for further procedures, became extremely weak, was given a drink and vomited. She inhaled the vomit and suffered a cardiac arrest resulting in brain damage. Plaintiff’s weakened state was due to pancreatitis and also defendant’s negligent lack of care.

Bonnington Castings v Wardlaw

Proposition: Material Contribution is defined as contribution that is not negligible.

Held: That the Df had materially contributed to the injury based on a balance of probabilities, even though but for test could not be proved, the contribution of the Df breach to the Pf illness was not negligible. Df liable for full extent of liability, but if the Df counsel had argued for apportioned liability due to the disease being divisible, would have succeeded.

Facts:

Pf employee was exposed to silicone dust as a result of Df employer’s breach in their failure to install effective safety measures. Pf suffered a cumulative illness from this. One source of exposure was by Df, and another was non-tortious.

Holtby v Brigham

Proposition: If the injury is divisible, the the liability is apportioned.

Held: Df was liable based on material contribution to damage test, even though the overall illness was materially contributed to by both negligent and non-negligent causes. Apportioned liability and reduced from 100% to 75%

Facts: Plaintiff employee worked for defendant employer for half of his working life and due to the latter’s negligence, he was exposed to asbestos dust. For the rest of his working life, he had worked for other employers who similarly contributed to his exposure to asbestos dust.

Yeo Peng Hock Henry v Pai Lily

Held: Factual Causation not made out.

Reasoning: patient has not proved, on a balance of probabilities, that had the doctor advised her to go to a hospital immediately and had she done as advised, the plaintiff’s eye would have been saved. Hence, causation was not made out.

Facts: Appellant was the respondent’s doctor. Appellant breached his duty by failing to advise the patient to go immediately to the hospital to seek treatment for her eye. Had antibiotics been administered earlier, the eye infection would have been prevented.

What are the different types of Causes?

*Answers the question of which test to apply
For Cumulative - Use material contribution to damage - Pf dont need to prove who had actually caused it - Just need to show that the breach had materially contributed to the damage on balance of probabilities - Science can prove that the Df added to the severity of the harm - Everyone contributed

For trigger - It is a all or nothing approach where just one strand of asbestos will lead to mesothelioma - Cannot use material contribution - Science cannot tell you who caused it - Only one tortfeasor actually caused it

Trigger Cause - Causal Mechanisms that result in greater damage or loss with greater exposure to the causal mechanism

• In the case of McGhee, where the exposure to brick dust will cause dermatitis [Material Increase to Risk]

• In the case of Fairchild, where at the time it was believed that the disease was caused by a single trigger therefore it was assumed that the exposure to asbestos dust will cause mesothelioma [Material Increase to Risk] - Therefore at the time could not use material contribution to damage

Cumulative Cause - Accretive Causal Mechanisms where there will be greater damage or loss with greater exposure to the causal mechanism

• In Bonnington, the Pf inhaled silica dust from two sources, one non-tortious source and one tortious source, Df breached duty in the tortious source, both sources cumulatively contributed to the damage. Pf just needed to show that the material contribution was material (not negligible) on a balance of probabilities. Note pnemonoconiosis is a divisible disease where liability can be apportioned

• In Holtby, asbestiosis is a cumulative condition caused by sequential exposure to asbestos over time therefore material contribution to damage test was used.

What are the various types of damages?

Divisible - Loss or damage suffered by the Pf can be divided and seperated into distinct components where several Df may be severally liable

• In Sienkiewicz, the Court argued in Bonnignton that pneumoconiosis is a divisible disease and if the Df had argued, there could be proportionate liability

• In Holtby, asbestiosis was cumulative in nature and divisible therefore the Court reduced the damages to 75% as the Pf worked for other employers who had exposed the Pf to asbestos as well.

Indivisible - Damage that cannot be divided resulting in all the Df being jointly liable in solidium

• In Bailey, the brain damage in this case was indivisible even though there was cumulative factors (hospital negligence, pancreatitis) - Df takes full liability [Material Contribution to Damage - But still can be indivisible - Brain damage]

• In McGhee, the brick dust was a trigger cause and dermatitis is an all or nothing disease where just a single exposure, the injury is complete and indivisible. Df 100% liable.

Summerise the Differences in Material Contribution to Damage and Material Contribution to Risk

For Contribution to damage, you must prove on a balance of probabilities that the Df had materially contributed (non negligible or de minimis) to the damage and had actually added on to the injury

For Contribution to risk, as you cannot prove that the Df actually contributed to the damage, you instead prove that the Df breach had materially increased the risk of the injury accentuating

• Can only be used for the same causal mechanism with multiple causal agents (Fairchild extension of Mcghee)

• Only to be used when human science on a balance of probilities prove that the injury was as a result of either employment by A or B or both [Material Contribution to Damage instead]