Climate activists will argue in an Oslo court this week that Norway's plans for Arctic oil exploration are unconstitutional, in an emerging branch of law where plaintiffs are trying to enlist a nation's founding principles to limit warming ...[such as] Article 112 of Norway's constitution [that] speaks of safeguarding a healthy environment for future generations.

...The Norwegian case, brought by Greenpeace and the Nature and Youth group, argues that a 2015 oil licensing round in the Arctic violates the constitution because Norway has agreed to the Paris accord's goals to end the fossil fuel era this century.

...Norway's attorney general argues that the oil licences, awarded to Statoil, Chevron, Lukoil, ConocoPhillips and others, have no link to the Constitution. Norway's environmental laws are among the toughest in the world.

...Environmentalists say the case is far more than a stunt. Losing could mean having to pay the state's legal fees, meaning a total bill exceeding $500,000.