Roll-call votes are central tools for studying legislative politics, but their representativeness remains questionable.

This article addresses two common defenses against concerns about roll-call sampling: its pervasiveness and the benign strategic incentives behind vote requests.

First, we analyze voting procedures across 145 chambers and find that roll calls are typically discretionary — meaning legislators decide when to use them. Second, we present a formal model showing how this method selection affects position-taking strategies.

Our findings reveal three key problems:

• Roll-call votes don't always capture all legislative decisions
• Strategic incentives can bias which bills get put to vote
• Measurement practices often lack transparency

These results suggest that scholars must more carefully consider the relationship between roll-call data collection and substantive political phenomena. The analysis highlights significant gaps in current approaches to measuring legislative behavior.