Pennsylvania Supreme Court Hears Oral Arguments on RGGI

Harrisburg, Pa., May 12, 2025 – The Pennsylvania Supreme Court will hear oral arguments tomorrow in Harrisburg on the constitutionality of the controversial Regional Greenhouse Gas Initiative (RGGI).  

Pennsylvania entered RGGI through then-Governor Tom Wolf’s unilateral action, where he usurped the legislature’s constitutional authority to levy taxes. The Commonwealth Court correctly ruled that RGGI was an unconstitutional tax. 

Governor Shapiro, at taxpayer expense, appealed the Commonwealth Court’s decision—despite his own statements on the campaign trail against RGGI—and asked the justices to reverse the Commonwealth Court ruling. A reversal by our high court will have calamitous consequences for Pennsylvania families. RGGI will cripple the commonwealth’s energy sector and raise electricity prices for Pennsylvania families and businesses. 

Regardless of the policy implications of RGGI, the court should affirm the lower court’s decision that the governor’s blatant executive overreach against the legislature was unconstitutional. It is not for the state’s top court to determine whether RGGI is a good policy. Instead, the court should weigh in only on the constitutionality of RGGI.  

The Commonwealth Foundation urges the Pennsylvania Supreme Court to uphold the lower court’s ruling and strike down the unconstitutional carbon tax, which was adopted without legislative approval. 

Commonwealth Foundation COO and General Counsel Megan Martin provided the following comments: 

“Former Gov. Tom Wolf unilaterally entered Pennsylvania into RGGI through unconstitutional executive overreach. Gov. Josh Shapiro continued this power grab when he appealed the Commonwealth Court’s decision. The Pennsylvania Supreme Court must uphold the rule of law and separation of powers, two fundamentals upon which our republic was built. Allowing the governor to usurp the power of the general assembly would set a dangerous precedent, encouraging Shapiro and future governors to ignore the Legislature and pursue more unilateral actions.” 

Commonwealth Foundation Senior Manager for Energy Policy André Béliveau provided the following comments: 

“RGGI is a tax on modern life. It punishes energy consumers, hinders economic growth, and manipulates the market in ways that greatly harm Pennsylvania’s economy with no clear positive environmental impacts. Energy policy is complex and needs robust debate by the people’s legislative representatives. This outcome means everything to Pennsylvanians, as RGGI sacrifices their quality of life in the name of misguided policy.” 

More information about RGGI is available on the Commonwealth Foundation’s website here.