This article explores how party-based issue ownership influences content within US congressional statutes (1947-2012) and State of the Union addresses, as well as UK acts of Parliament and Queen’s Speeches (1950-2010). Using time-series analyses, it identifies three conditions where executive incentives to pursue party-owned issues are constrained: responsiveness to public priorities, stronger electoral mandates, and divided government. The findings offer strong support for the theory in both systems but highlight notable institutional differences, providing insights into when governments focus exclusively on partisan issue priorities.