### The Core Question

This article examines a crucial tension in political representation. While proportional electoral systems excel at capturing diverse public policy preferences, they may simultaneously harm the quality of selected legislators.

### A Swiss Case Study

To explore this trade-off empirically, we analyze Switzerland's early 20th century transition to more intensive forms of proportional representation.

### Clever Measurement Approach

We overcome concerns about endogeneity by exploiting natural variation in reform implementation. This method uses administrative constraints and voter preference data.

### Key Findings & Significance

Our analysis shows policy congruence with voters increases while legislative quality indicators decrease. The European Parliament's modern patterns support these century-old findings, suggesting a persistent trade-off between representation types.