Rylands v. Fletcher
House of Lords
L.R. 3 H.L. 330 (1868)
Fletcher (plaintiff) operated underground coal mines on land next to property where Rylands (defendant) built a reservoir to supply water to his mill, hiring engineers and contractors who discovered, unbeknownst to Rylands, that the reservoir sat atop abandoned coal mines. After completion, the reservoir broke and flooded Fletcher's mines, damaging his property. Fletcher sued Rylands; the Court of Exchequer held Rylands not liable, but the Court of Exchequer Chamber reversed and held Rylands strictly liable for the flood damage, and Rylands appealed to the House of Lords.
Whether a person who disrupts the natural state of real property by lawfully bringing something onto his land that, if it escapes, can potentially do harm, is strictly liable for any harm caused by the escape.