Regulatory reform of passengers public transport in Brazil: Public authorities or independent agencies?

In this paper, we approach the roles played by independent regulatory agencies in the new regulatory scene being implemented fdr the provision of infrastructures, specially public transport. Moreover, the paper addresses main questions concerning to relationships between regulatory agencies and public authorities, private or public operators and service consumers, specifically in Brazil, where the public service approach to public transport has been applied for almost a century, what should be the sphere of influence, goals and tasks of independent regulatory agencies? Is there a real necessity of these institutions where public transport has a long tradition of being regulated and managed by public authorities while operated by private enterprises? How could an independent agency replace public authorities in the task of guaranteeing service quantities and quality as desired by people?