What legal principle does Rylands v Fletcher establish?

The legal principle established by Rylands v Fletcher is focused specifically on liability for the escape of non-naturally stored materials that cause damage. This case introduced the doctrine of strict liability in tort, which holds a party responsible for damages caused by hazardous activities or substances they keep, regardless of the level of care they may have taken to prevent such occurrences.

In Rylands v Fletcher, the defendant had built a reservoir that burst and flooded the plaintiff's coal mines. The court found that the defendant was liable for the damage caused by the escape of water, as it was a non-natural use of land. This case is particularly significant because it highlights that liability can arise even when there is no negligence involved; the mere fact of maintaining a dangerous substance creates an obligation to ensure that it does not escape and cause harm.

This contrasts with the other choices. Claims of strict liability for any acts causing damage or conditional liability based on negligence involve broader or different contexts of liability than what Rylands v Fletcher specifically pertains to. Similarly, the choice regarding protection for property owners from any trespass does not encapsulate the core principle that the case addresses, which is narrowly focused on the escape of dangerous substances rather than general property rights or trespass issues.