Antitrust policy has been increasingly considered as relevant mechanism of economic welfare promotion in recently liberalized oligopolistic markets. The purpose of this paper is to develop a structural model, in order to investigate alleged price coordination by the airlines on the air shuttle route Rio de Janeiro - São Paulo. By making use of a conduct parameter, based on the New Empirical Industrial Organization approach, it was possible to focus on the effects of the formation of an alleged cartel instead of relying on evidence of collusion such as previous communication between the involved companies. Results achieved using a Two-Step Estimator indicated no basis for rejecting the hypothesis that firms kept non-cooperative conduct in the market, contrary to recent decision by the Brazilian antitrust authorities.
