Throughout the Obama Administration, state attorneys general (AGs) have collaborated on several high-profile political issues. To get a fuller picture of this contemporary AG activism, this article analyzes AG participation in lawsuits and amicus curiae briefs before the U.S. Supreme Court across three presidential administrations. The results suggest that AGs’ agendas have increasingly diverged throughout the Obama Administration, reflecting greater vertical conflict between AGs and the federal government as well as horizontal conflict among AGs themselves. Several factors have contributed to this development, including the broader polarization of American politics, intensified activism among Republican AGs, and increased collaborations between AGs and ideological interest groups. Much as with partisan contestation in other venues, these AG conflicts show few signs of abating
