Introduction

The case of Alasdair Kerr and others against Midlothian Council and another ([2024] CSOH 112) presented before the Scottish Court of Session on December 20, 2024, delved into the complex intersection of occupational health, statutory duties, and causation in asbestos-related disease claims. Mrs. Sarah Kerr, a former chemistry and science teacher, succumbed to epithelioid malignant peritoneal mesothelioma in June 2022. Her family contended that her prolonged exposure to asbestos during her teaching tenure at Midlothian Council and Moray Council schools led to her fatal illness. This commentary explores the court's comprehensive analysis of liability, causation, and the applicability of established legal precedents in determining the validity of asbestos exposure claims.

Summary of the Judgment

The central issue in the case was whether Mrs. Kerr's employers breached their duty by exposing her to asbestos, thereby materially increasing her risk of developing peritoneal mesothelioma. The court meticulously examined expert testimonies regarding the nature and extent of asbestos exposure, the potency of different asbestos fibers, and the epidemiological evidence linking asbestos to peritoneal mesothelioma. Ultimately, Lord Malcolm concluded that the evidence did not establish a material increase in risk sufficient to impose liability on the employers. The court affirmed the strict standards required to apply the Fairchild exception in cases involving rare disease forms and low-level exposures.

Analysis

Precedents Cited

The judgment referenced several key precedents that shaped the court's reasoning:

• Sienkiewicz v Greif (UK) Ltd [2011] 2 AC 229: Established the test for joint and several liability in asbestos cases, focusing on 'material increase in risk'.
• Fairchild v Glenhaven Funeral Services Ltd [2003] 1 AC 32: Introduced the special causation rule for asbestos claims where the exact cause of mesothelioma cannot be pinpointed.
• Bussey v Anglian Heating Ltd [2018] EWCA 243: Clarified the foreseeability and material increase in risk standards.
• Sanderson v Hull [2009] PIQR P7 (CA): Summarized the application conditions for the Fairchild exception.
• Williams v The University of Birmingham [2012] PIQR P4 (CA): Distinguished cases involving multiple causative factors.
• Bannister v Freemans Public Ltd Co [2020] EWHC 1256 (QB): Discussed methods for assessing materiality in risk increase.

These precedents collectively emphasize the necessity of demonstrating a material increase in risk and restrict the Fairchild exception to narrowly defined circumstances, predominantly involving pleural mesothelioma and clear asbestos causation.

Legal Reasoning

The court's legal reasoning centered on the interpretation and application of the Fairchild exception. Key points included:

• Causation: The court scrutinized whether asbestos exposure was a sufficient factor in Mrs. Kerr's rare peritoneal mesothelioma, given the low levels of exposure and the predominance of chrysotile fibers, which have a weaker association with this disease.
• Material Risk: It was determined that the estimated asbestos exposure did not constitute a material increase in risk. The cumulative exposure fell significantly below levels recognized to pose meaningful health hazards.
• Fairchild Exception Applicability: The court concluded that the exception was unsuitable for this case due to the inability to establish asbestos exposure as a causative factor for the specific type of mesothelioma.
• Epidemiological Evidence: Reliance on the Hodgson and Darnton study highlighted the challenges in linking low-level chrysotile exposure to peritoneal mesothelioma, reinforcing the court's skepticism about causation in this context.

Impact

This judgment reinforces the stringent criteria for establishing liability in asbestos-related claims, especially concerning rare disease forms like peritoneal mesothelioma. It underscores the necessity for clear causation links and a demonstrable material increase in risk. Consequently, future cases involving low-level asbestos exposure and uncommon disease manifestations may find similar hurdles in proving employer liability.

Additionally, the decision emphasizes the importance of distinguishing between different types of asbestos fibers and their respective health risks, potentially influencing occupational safety standards and employer practices regarding asbestos management.

Complex Concepts Simplified

Fairchild Exception

Originally established in Fairchild v Glenhaven Funeral Services Ltd, the Fairchild exception allows claimants to bypass the traditional requirement of proving causation in asbestos cases. Instead, if an employer's negligence materially increased the risk of developing mesothelioma, they can be held liable, even if it cannot be proven that their specific actions caused the disease.

Material Increase in Risk

A "material increase in risk" refers to a significant, non-trivial rise in the probability of a claimant developing a disease due to the defendant's actions. In asbestos cases, this often means exposure levels that markedly elevate the likelihood of conditions like mesothelioma.

Causation vs. Contribution

Causation requires establishing that the defendant's conduct directly caused the claimant's injury. In contrast, contribution refers to the defendant's role in increasing the risk of injury, even if it's not the sole cause.

Epidemiological Evidence

This involves statistical studies that examine how exposure to certain factors (like asbestos) correlates with the incidence of diseases. In this case, epidemiological data was crucial in assessing whether asbestos exposure was likely to have contributed to Mrs. Kerr's mesothelioma.

Conclusion

The Alasdair Kerr case serves as a pivotal reference point in asbestos litigation, particularly concerning rare forms of mesothelioma and low-level exposure scenarios. By reaffirming the stringent demands for establishing a material increase in risk and appropriate causation, the court delineates the boundaries within which the Fairchild exception operates. This ensures that liability is only imposed when there is substantial evidence linking occupational negligence to the claimant's injury, thereby maintaining legal clarity and fairness in complex health-related claims.