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Sunlight disinfects—but beware of the shade

Leopoldo Fergusson and Juan Fernando Vargas

By providing information, mass media can help voters make better decisions and hold politicians accountable. Often, journalists also help uncover corruption scandals and undue influence of special interest groups. Many argue that the active, informative press in the United States during the so-called Progressive Era reduced corruption and mobilized the population against the power and abuses of robber barons. 

It was also during the Progressive Era that Louis Brandeis famously remarked, ‘Sunlight is said to be the best of disinfectants.’ Earlier, Thomas Jefferson had gone so far as to say that free media is sufficient for political accountability: ‘Where the press is free, and every man able to read, all is safe.’ 

In a recent paper with Mauricio Vela (Inter-American Development Bank), we argued that Jefferson’s statement is incomplete: free media is no guarantee of political accountability. In particular, we argue that unless it operates in a sufficiently strong institutional environment, the free media’s provision of information about politicians may not increase political accountability and may even have unintended negative consequences.

To capture the essence of our argument, imagine a situation where two politicians compete in an election. One of the politicians coerces a fraction of voters to vote for him. A free and active press, in turn, exposes this politician, revealing his electoral malpractices.

What happens next? Presumably, the existence of this information means that the politician will become less popular among free voters. However, the corrupt politician might also increase his coercion efforts to counteract the impact of the media scandal. If the retaliatory coercion is strong enough, the media scandal may not even reduce the votes for the exposed politician.

In our study, we show that this is not merely a theoretical possibility—it is exactly what happened in Colombia's legislative elections from 2002 to 2010. During the ‘parapolitica’ (para-politics) scandal, the national media denounced politicians who partnered with illegal armed paramilitary groups to obtain votes through coercion.

Our research first documents the phenomenon whereby the vote distribution ‘parapoliticians’ is different to that of non-parapoliticians. This is in line with what could be expected, namely that Senate candidates involved in the scandal receive significantly more votes in areas where paramilitary presence is higher and available institutions are inefficient.

Most importantly, the pattern is similar if we focus on the sample of parapoliticians and compare the vote distribution of candidates exposed by the media before elections took place, to the vote distribution of candidates exposed after they have been elected. Consistent with our argument, the former candidates concentrate their votes in areas in which coercion is easier to exert (i.e., places with more paramilitary presence, less state presence, and more judicial inefficiency). Ultimately, even with media exposure, parapoliticians are more successful than their clean competitors in getting votes.

It is clear that the power of mass media is a double-edged sword. Unbiased, free media of the kind Jefferson imagined helps achieve political accountability, but the opposite occurs when political capture, the profit motive, or other reasons bias its content.

Nevertheless, our findings go beyond this idea, and highlight the complementarity between the different dimensions of institutions in democracy: even if mass media provides valuable information to voters and thus increases transparency, it may not promote political accountability in a weakly-institutionalized environment where free elections are not guaranteed.

To complement Brandeis’s famous remark, sunlight may well be the best of disinfectants, but not when germs can hide in the shade. In Colombia, the media exposure of candidates involved in parapolitica sent them into the shade: they found the votes necessary to be elected in places with inefficient institutions and less state presence.


This blog post is published as part of a collaborative partnership between SIPRI and Economists for Peace and Security (EPS).