High Court issues landmark ruling against BHP over Brazil’s Mariana dam disaster: What it means for cross-border litigation
Last week – ten years after the Fundão Dam disaster, widely described as Brazil’s worst environmental catastrophe – London’s High Court ruled that the global mining company BHP Group is strictly liable. On 5 November 2015, the Fundão Dam in Southeast Brazil collapsed, releasing millions of tonnes of liquefied ore tailings into the environment in a catastrophic flow slide. The disaster killed 19 people and caused immense environmental and socioeconomic damage. This perspective examines what the case reveals about the possibility of seeking redress before English courts for corporate acts and omissions occurring abroad.
Establishing jurisdiction: Why and how in England and Wales
The claim was filed in England in 2018 and was brought against BHP Group (UK) Limited (“BHP UK”), domiciled in the UK, and BHP Group Ltd (“BHP Australia”), which – despite being non-domiciled – was found to carry on business in the UK and therefore had sufficient presence in the jurisdiction for the claim to be pursued against them. A group company, BHP Brasil Ltd (“BHP Brasil”) held a 50% stake in Samarco Mineração SA (“Samarco”), the company that owned and operated the dam. The ultimate parent of BHP Brasil was BHP Australia. At the relevant time, BHP UK and BHP Australia operated as a single economic entity under a dual-listed company structure. This created a “real and substantial” connection, allowing litigation to proceed in England and Wales. On that basis, the Court of Appeal held that England was an appropriate forum.
Who can bring claims and how Brazilian proceedings impact them
The English proceedings followed individual claims and class actions (CPAs) brought in Brazil. The largest Brazilian group action had been stayed since January 2017 pending negotiations. Although significant compensation and remediation programmes were implemented, many affected individuals remained dissatisfied with the remedies available in Brazil.
This prompted a group action in the UK initially involving around 200,000 claimants. The action has since grown to more than 600,000 individuals, including Indigenous and Quilombola community members, municipalities, faith-based institutions, businesses, and utility companies.
Before the liability trial, the defendants applied to strike out the claim as an abuse of process, arguing the claim was duplicative of the Brazilian proceedings and asserting that the scale of the English case rendered it “unmanageable.” Whilst BHP was initially successful in the High Court, this was overturned on appeal. The Court of Appeal emphasised that the potential size or complexity of a claim cannot restrict access to justice, and that the proceedings in England were not oppressive, as they involved different corporate entities to those in the Brazilian proceedings. Importantly, the Court of Appeal held that the English proceedings provide a “realistic prospect of a trial yielding a real and legitimate advantage for the claimants”.
At the liability stage, the High Court reviewed a sample of the compensation agreements signed in Brazil to assess their impact and scope on the claims in England. BHP argued that approximately 200,000 claimants had received compensation, signing full releases discharging their claims. As this ruling concerns liability only, the High Court held that full examination of the factual circumstances surrounding each agreement was outside the scope of this trial – however, on review of the sample before it, the High Court indicated that some of the settlement agreements were adhesion contracts, in other words standard-form agreements drafted by the party who has greater bargaining power than the other. The High Court held that any ambiguities or conflicts in such agreements must be interpreted in favour of the claimants. The High Court also made clear that neither the design of the compensation scheme nor the involvement of lawyers guarantees that a settlement agreement is valid.
How the English High Court found BHP liable under Brazilian Law
Although the proceedings took place in England and Wales, Brazilian law applied to the substance of the claims. Liability was assessed under three potential bases of Brazilian law:
- Strict liability based on BHP’s ownership or control of Samarco, BHP’s involvement in activities leading to the collapse, and/or the benefits it derived from those activities.
- Fault-based liability for negligent or imprudent acts or omissions, including (a) disregarding warnings about the risk of collapse, and (b) failing to take adequate action to prevent it.
- Corporate-law liability for abuse of power as controlling shareholders, in permitting activities that posed significant risks to the community.
The Court found BHP strictly liable as a matter of Brazilian law, under the “polluter pays” principle and also liable in fault, concluding that its acts or omissions were a direct and immediate cause of the dam’s collapse. However, the Court rejected the corporate-law liability argument, holding that the relevant provisions do not create autonomous duties owed by controlling shareholders to third parties. The Court dismissed BHP’s defence on limitation and on standing (in relation to the Municipalities – local government bodies in Brazil).
What this means moving forward
This landmark ruling demonstrates the willingness of English courts to adjudicate environmental harm occurring abroad and provides a powerful precedent for similar transnational claims in England and Wales.
Claims of this magnitude involve considerable complexity and require substantial time and resources. A second phase – addressing causation and quantum – is scheduled to begin in the High Court in October 2026, with a potential third phase in which individual claimants may need to prove their specific losses. BHP has also announced its intention to seek permission to appeal the liability judgment. Because the reasoning turned partly on specific provisions of Brazilian law, outcomes in such cases will remain fact-specific.
Despite these complexities, the Mariana dam proceedings have demonstrated such claims can succeed and that meaningful redress for large-scale environmental harm is achievable through the English courts.