This Comment explains why—despite the state’s adoption of the ERA in 1971 and the ERA’s seemingly clear, environmentally friendly language—the ERA did not have teeth until June 2017. This Comment begins with a history of the ERA, including its adoption and Pennsylvania courts’ early interpretations of it. It then describes the Pennsylvania courts’ environmentally destructive interpretation of the ERA and the eventual evolution of that interpretation. Finally, this Comment discusses the potential for using the ERA to compel the Commonwealth to regulate GHG emissions following two monumental 2017 Pennsylvania Supreme Court decisions—Pennsylvania Environmental Defense Foundation v. Commonwealth (PEDF) and William Penn School District v. Pennsylvania Department of Education (William Penn).