This study asks whether legislators change their votes when informed about an interest group’s size, economic importance and sectoral reach. Using a combination of a field experiment that randomized messages from a pro‑reform business organization, a survey experiment with lobbyists, and in‑depth interviews with senior political actors, the article tests whether informational cues about group characteristics increase legislators’ support. The contribution is a mixed‑methods, realistic test of cue‑based informational lobbying in a Brazilian setting, triangulating experimental and qualitative evidence without overclaiming generalizability.
Field experiment Survey experiment Mixed methods Interest groups
Data and methods
The core empirical design combines a field experiment in Brazil that randomized which legislators received printed and WhatsApp messages from a pro‑reform business organization, a supporting survey experiment administered to lobbyists, and in‑depth interviews with political figures (including a former president, ministers, and deputies). The abstract identifies the treatment variation as emphasis on the group’s membership size, economic importance, and sectoral reach.
Main findings
Across the mixed‑methods evidence, messages that highlighted group characteristics—membership size, economic importance and sectoral reach—were associated with greater legislator support for the group’s position in the field experiment. The survey experiment with lobbyists provided supportive evidence for the proposed mechanism: messages emphasizing group characteristics increased expectations of legislators’ engagement and support. Interviews with senior political actors corroborated these patterns qualitatively.
- Treatments emphasized membership size, economic importance and sectoral reach.
- Evidence comes from a field experiment, a survey experiment, and elite interviews.
