Justices and Political Loyalties: An Empirical Investigation of the Supreme Court of the Philippines, 1987–2020

The Philippine Supreme Court is considered one of Asia’s most activist courts. During the regime of President Rodrigo Duterte (2016–22), however, concerns grew about its independence. This article investigates determinants of the Court’s behavior since the country’s return to democracy in 1987, with particular attention to “loyalty effects”— the likelihood that justices will vote for the government more often when the president who appointed them is in office. Drawing on a data set of seventy major political cases and sociobiographic profiles of the eighty-six justices who voted in them, we test for variables, including freshman effects and strategic defection toward the end of a presidential term. We find that early years on the bench are closely associated with a vote for the appointer’s administration, and the end of a presidential term is weakly associated with a vote against. Under the Duterte administration, voting preferences have been more aligned with the appointer, and factional alliances of justices appointed by different presidential administrations mirror political alignments. These results have practical implications for the fragile constitutional democracy in the Philippines and contribute to understanding of loyalty dynamics in less institutionalized judicial settings.