Four days before Justice Antonin Scalia died on Saturday, the 79-year-old justice and the court's four other conservatives blocked one of President Barack Obama's centerpiece packages—his climate change initiative requiring a 32-percent reduction in power plant emissions by 2030.

More than two dozen states and energy companies are suing to thwart the plan, claiming that Obama's carbon regulations announced in October are an abuse of power and will "unlawfully impose massive and irreparable harms upon the sovereign states, as well as irreversible changes in the energy markets." The Supreme Court's decision to block the plan from taking force ahead of June 2 oral arguments before a federal appeals court was viewed as an ultimate death blow of sorts to the plan. The 5-4 conservative majority sided with the states and essentially said that the regulations are shelved until the Supreme Court lifts its stay.

Coal-burning plants generate about a third of the nation's power and are the hardest hit by Obama's regulations. West Virginia and Kentucky, two of the states that rely heavily on coal for power and jobs, initiated the legal challenge to the Clean Power Plan. Utilities are the nation's largest source of carbon emissions.

The US Court of Appeals for the District of Columbia Circuit will hear oral arguments on the carbon plan on June 2, Obama announced in October. Whatever the outcome, the legal challenge will almost certainly go upstairs to the Supreme Court. If there's still a vacancy on the bench when the case reaches the high court, the outcome will likely be a 4-4 vote. In the case of a tie, the lower court's decision will stand. And the lower court's three-judge judicial panel, chosen at random, includes two Democratic appointees and one Republican. That three-judge panel has already voted to allow the regulations to become the law of the land while the legal challenge to them proceeds before those three judges. That's a strong indication that the appellate panel will ultimately uphold Obama's climate change plan in the aftermath of the June 2 oral arguments.

And here's where the tea leaves get harder to read. It's a safe bet that the Supreme Court will uphold the plan if Obama somehow gets a Scalia successor on the bench before the Obama presidency expires on January 20. It's also possible that political wrangling could thwart Obama's choice before he leaves office. That means the most junior member of the high court will be chosen by the next president—whomever that may be—and will cast the swing vote on Obama's climate change plan.