This note addresses a pervasive issue in political science research on judicial selection. The classification problem stems from three key sources: ambiguous theoretical arguments, inconsistent decision rules for categorizing merit selection states, and failure to account for interim selections within mixed systems.

To illustrate the practical implications of this classification challenge, I replicate an existing study on opinion writing productivity in state supreme courts. This replication demonstrates the potential threats to sound inference that can arise from these methodological inconsistencies.

The author offers straightforward suggestions for mitigating this problem. Resolving it is essential because eliminating the classification issue will significantly improve our ability to compare findings across different studies of state judicial selection mechanisms, ultimately enhancing understanding of how institutional design choices affect court outcomes.