SAN FRANCISCO — To some, Cotchett, Pitre & McCarthy’s massive climate-change lawsuit, which lists both the United States of America and President Barack Obama as defendants, may seem like an absurd overreach.The 100-page complaint, filed this summer, seeks to hold the government accountable for global warming and force the president to implement a plan to cut carbon emissions. It’s a constitutional claim: 21 child and teenage plaintiffs have been deprived of their Fifth Amendment right to life, liberty and property by the government’s failed environmental policy, the complaint asserts. Already the Cotchett team finds itself squaring off against powerful foes—a group of oil industry associations represented by Sidley Austin has attempted to intervene and file a motion to dismiss.

It promises to be an immensely difficult and complex case, and one with no clear-cut promise of damages or attorney fees. Even Joseph Cotchett himself has said he expects it will “get thrown out initially.”