New research disputes the long-held view that constitutional amendment rules are unimportant. This article introduces a novel index measuring constitutional rigidity across ninety-four democratic countries, built using the Veto Players approach.

Addressing Disagreements: The author argues previous empirical studies misapplied variables and methodology regarding constitutional change.

Methodological Approach: By aggregating institutional provisions through the Veto Players lens, this work quantifies constitutional rigidity in a logical way.

Understanding Significance: The article clarifies that while low rigidity is necessary for meaningful constitutional amendments to occur, it does not guarantee them.

New Findings: Analyzing ninety-four democratic nations and their constitutional changes reveals the importance of amendment significance. A heteroskedastic model shows better fit when more substantial amendments are considered.