The judgment was unanimous though not all the justices signed on to the prevailing opinion.
The Nigerians originally were residents of Ogoniland, an area of 250 square miles in the Niger delta, populated by roughly 500,000 people.
Named in their suit were the Royal Dutch Petroleum Co. and Shell Transport and Trading Co., holding companies incorporated in the Netherlands and England, respectively. Their joint subsidiary, named in the complaint, the Shell Petroleum Development Co. of Nigeria Ltd., was engaged in oil exploration and production in Ogoniland.
The complaint said after concerned residents of Ogoniland began protesting the environmental effects of the subsidiary's practices, the companies "enlisted the Nigerian government to violently suppress the burgeoning demonstrations." Throughout the early 1990s, the complaint alleges, "Nigerian military and police forces attacked Ogoni villages, beating, raping, killing, and arresting residents and destroying or looting property."
The complaint says the companies "aided and abetted these atrocities by, among other things, providing the Nigerian forces with food, transportation, and compensation, as well as by allowing the Nigerian military to use [their] property as a staging ground for attacks."
The Nigerians moved to the United States where they were granted political asylum.
They filed suit under the U.S. Alien Tort Statute, hoping to hold the companies accountable for the alleged conduct, but eventually a federal appeals court in New York dismissed all the claims, saying the ATS does not recognize corporate liability.
The U.S. Supreme Court agreed with the appeals court in a unanimous judgment, saying the appeals court correctly interpreted the law.
The prevailing opinion by Chief Justice John Roberts said: "Passed as part of the Judiciary Act of 1789, the ATS is a jurisdictional statute that creates no causes of action. It permits federal courts to 'recognize private claims [for a modest number of international law violations] under federal common law."
All the justices concurred in the judgment, though several did so in a separate opinion, not signing on to Roberts' opinion.