This study explores how the interests of the oil and gas industry are represented in the Brazilian Congress. Specifically, it examines the performance of parliamentarians associated with groups such as the Parliamentary Front in Support of Oil, Gas, and Energy; the Parliamentary Front for the Sustainable Development of Oil and Renewable Energies; and the Joint Parliamentary Front for Natural Resources and Energy; and the Joint Parliamentary Front in Defence of Oil Exploration in the Equatorial Margin of Brazil. It analyses how their voting patterns compare with those of other members of Congress on key energy and environmental issues. The hypothesis underlying this study is that congressmen belonging to these fronts may have voted more strongly against initiatives aimed at a rapid transition to cleaner energy, even if such efforts were ultimately unsuccessful.