"The more these lawsuits succeed, the more that puts pressure on the industry groups to support comprehensive climate legislation, or at least not oppose it," says Jonathan Zasloff, an expert in tort and environmental law at the University of California-Los Angeles.

All three suits rely upon the theory that climate change is a public nuisance and, therefore, state and local governments, as well as individuals who have been harmed, can sue for damages or injunctions. They also make arguments that proved successful against the big tobacco companies in the 1990's arguing corporations conspire to create a false scientific debate about global warming in order to deceive the public. ExxonMobil, for example, is accused of channeling $16 million over a seven-year period to 42 organizations that promote false information on global warming.

All three cases were dismissed by the District Courts. Connecticut and Comer were reinstated on Appeal and are scheduled for further review by the U.S. Supreme Court. The appeal of Kivalina is still pending.

"If the Court does not act on Connecticut or Comer, I think Kivalina will go forward. I think that one could end up being the most dangerous of any of them. But getting into court is one thing; proving causation is a very hard row to hoe," stated Environmental litigator Steven Jones.