Political economy of mass media : public good, news and voting behaviour

In every democracy mass media play a crucial role in assuring the effective working of the political system. In this paper I focus on the role of media as "watchdog". In an agency relationship between politician and citizens, media perform the function of an informed supervisor. Previous works have assumed that all the information available to citizens about the incumbent politician is channelled through mass media only. This work investigates how citizen's voting decision and collusion between media and politicians change if two pieces of information about the politician are available: media information and a good publicly supplied. My findings are: i) by employing both the two signals, citizens manage to sort out honest politicians from dishonest ones more often than if they were relying on media information only; ii) collusion is harder to take place than in the case of one signal only; iii) the presence of media is not always welfare improving, contrary to previous literature findings. Finally, I argue that when rules at the constitutional level are not possible and citizens cannot commit to have less information, then collusion between media and politician can be welfare improving for citizens. -- Mass Media ; Corruption ; Selection and Discipline of Politicians