The case of Deep Vein Thrombosis and Air Travel Group Litigation ((2006) 87 BMLR 1) before the United Kingdom House of Lords revisits the interpretation of the term "accident" within Article 17 of the Warsaw Convention 1929. This litigation addresses whether Deep Vein Thrombosis (DVT), commonly associated with long-haul flights due to prolonged immobility, qualifies as an "accident" that would render air carriers liable for bodily injuries sustained by passengers.

The principal parties involved include a group of claimants alleging that their DVT was caused by the conditions of air travel managed by various commercial airlines, thereby seeking compensation under the Warsaw Convention. The key issue centers on the scope and definition of "accident" as it applies to DVT resulting from standard flight operations.

The House of Lords unanimously dismissed the appeal brought forward by the group of claimants. The Lords held that DVT does not constitute an "accident" under Article 17 of the Warsaw Convention when it arises solely from the normal operation of an aircraft. The court emphasized that for an event to qualify as an "accident," it must be an unexpected or unusual occurrence external to the passenger.

The judgment underscored that the conditions contributing to DVT, such as cramped seating and prolonged immobility, are inherent to standard flight operations and do not meet the threshold of being "unexpected" or "unusual." Consequently, airlines cannot be held liable under Article 17 for such injuries unless they can demonstrate that an external, unforeseen event caused the harm.

Precedents Cited

The judgment extensively references prior cases that have shaped the interpretation of "accident" under international aviation law:

• Morris v KLM Royal Dutch Airlines [2002] AC 628 – Highlighted the importance of uniform interpretation across signatory states.
• Sidhu v British Airways plc [1997] AC 431 – Established that without an "accident" under Article 17, no other remedy is available.
• El Al Israel Airlines Ltd v Tsui Yuan Tseng 525 US 155 (1999) – Reinforced the exclusivity of Article 17 remedies.
• Air France v Saks 470 US392 (1985) – Defined "accident" as an unexpected or unusual event external to the passenger.
• Povey v Qantas Airways Ltd [2005] HCA33 – The Australian High Court mirrored the English Court of Appeal, ruling that DVT does not qualify as an "accident."
• Olympic Airways v. Husain 124 S.Ct. 1221 (2004) – Addressed whether inaction (e.g., not relocating a passenger) can constitute an "accident."

Legal Reasoning

The House of Lords' reasoning hinged on the following key points:

• Definition of "Accident": The court adopted a definition consistent with Air France v Saks, positing that an "accident" must be an unexpected or unusual event external to the passenger, not merely the consequence of them being subjected to standard flight conditions.
• Strict Liability Framework: Article 17 imposes strict liability on carriers without the need to prove negligence. However, this liability is contingent upon the occurrence of an "accident."
• Exclusion of Internal Causes: Medical conditions or internal bodily reactions (like the formation of blood clots) are not considered accidents unless triggered by an external, unexpected event.
• Uniform Interpretation: Emphasized the necessity for a consistent application of the Convention across different jurisdictions to maintain its efficacy as a harmonizing international treaty.
• Limitations Under Article 20 and 21: Even though Articles 20 and 21 allow for defenses based on carrier's measures and contributory negligence, they do not override the fundamental definition of an "accident" required for liability under Article 17.

Impact

This judgment has significant implications for both passengers and airlines:

• Passengers: Passengers suffering DVT cannot seek compensation under Article 17 unless they can link their condition to an unexpected external event aboard the aircraft, thereby limiting recourse through international treaties.
• Airlines: Airlines are generally shielded from liability for DVT under Article 17, provided they adhere to standard operational practices, reducing potential legal exposure from common health-related complaints.
• Future Litigation: Sets a clear precedent that internal bodily conditions arising from standard flight operations do not constitute accidents, guiding future courts in similar cases.
• Regulatory Practices: Motivates airlines to follow and possibly enhance industry safety standards, though not through Article 17 liability, but through other regulatory and competitive pressures.

Article 17 of the Warsaw Convention

Article 17 outlines the circumstances under which an airline (carrier) is liable for passenger injuries. It stipulates that the carrier is liable for death or bodily injury if an "accident" causes such damage during the flight or during boarding and disembarking operations.

"Accident" Defined

An "accident" is not merely any event that occurs on a flight. It must be an unexpected or unusual event external to the passenger. This excludes injuries that result from standard conditions of flight, such as cramped seating leading to DVT.

Strict Liability

Under Article 17, airlines are held liable for certain passenger injuries without the need to prove negligence. However, this liability is strictly tied to whether the injury was caused by an "accident" as defined by the Convention.

Exclusions Under Articles 20 and 21

- Article 20: Allows carriers to avoid liability if they can prove they took all necessary measures to prevent damage.
- Article 21: Accounts for cases where the passenger's own negligence contributed to their injury, potentially reducing the airline's liability.

The House of Lords' decision firmly establishes that Deep Vein Thrombosis (DVT), arising from the inherent conditions of air travel, does not qualify as an "accident" under Article 17 of the Warsaw Convention. This interpretation aligns with a consistent global judicial stance that shields airlines from liability for injuries resulting from standard flight operations, provided no unexpected or external events trigger such harm.

This ruling underscores the importance of precise legal definitions in international conventions and reinforces the principle of limited liability for carriers in the context of passenger injuries. For passengers, it delineates the boundaries of legal recourse available under international air travel law, while airlines can continue to operate with a clearer understanding of their liability exposures.

Ultimately, the decision promotes a balanced approach, safeguarding the interests of both passengers and carriers by defining clear criteria for when airline liability is invoked, thereby contributing to the stability and predictability of international aviation law.