Editor’s Note: This is the sixth post in a series drawn from a new Journal of Peace Research special issue on “Communication, Technology, and Political Conflict.” The entire special issue has been made available by Sage Publications here. For earlier posts, see herehere, here, here, and here

As the recent wave of protests in Hong Kong was making headlines across the world, Chinese and Russian state media initially barely covered the events, and later portrayed them as a U.S.-organized plot. During last winter’s protests in Ukraine, Western media emphasized the anti-corruption message of peaceful protesters in the square, while Russian media focused on Molotov cocktails being thrown at police by far-right nationalists. In the early stages of the Syrian Civil War, the Washington Post continued to refer to Syrian rebels as an “overwhelmingly peaceful protest movement,” even after hundreds of Syrian troops had been killed.

Reporting bias — the tendency to systematically under- or over-report certain types of events — shapes our understanding of war. In addition to producing much of the information available to government agencies, protesters, citizens and rebels, news organizations generate the data social scientists use to study political movements. If media sources systematically differ in their accounts of domestic and interstate conflict, then this divergence should be highly consequential for public knowledge, policy, and scientific inference.

In our article in a recent special issue of the Journal of Peace Research, we examined patterns of global news coverage during the 2011 Libyan civil war. We uncovered evidence of a pro-incumbent-government media bias in non-democratic states, and a pro-challenger bias in democratic states. Media coverage in non-democracies under-reported stories likely to generate sympathy for anti-regime rebels, like protests and nonviolent collective action by regime opponents. News outlets in such countries largely ignored stories casting the regime in a negative light, like government atrocities, and over-reported atrocities caused by rebels. We found the opposite patterns in democratic states — spikes in news reports immediately following the killing of civilians by government troops, yet no such spikes following similar actions by the rebels.

Bottom line: coverage of protest and civil conflict is likely to be “one sided” in both democracies and autocracies, but for different reasons. While the media in democracies typically are relatively independent from government influence, they have their own institutional biases — such as “newsworthiness” criteria that emphasize novelty, conflict, proximity, and drama. In civil conflicts, these preferences generate disproportionate coverage of developments and movements that challenge the regime, and underscore the unsustainability of the status quo.

In non-democracies, where governments frequently own or influence media firms, news coverage is more likely to reflect the regime’s preferences for political self-preservation, emphasizing the legitimacy and stability of the prevailing order. Mobilization against peer autocratic regimes, through its example, can raise regime opponents’ expectations that domestic state authority could be successfully challenged. This provides non-democratic leaders with strong incentives to suppress any news coverage that might result in emulation efforts at home.

These patterns emerged in our analysis of new data, containing every article on Libya published by 2,252 newspapers in 113 countries between Dec. 18, 2010 (the first day of protests in Tunisia, which ignited the Arab Spring) and Oct. 23, 2011 (three days following the capture and death of Muammar Qaddafi). We investigated whether the type and intensity of violence on the ground predicted the timing of these 213,406 articles, across the countries in our sample.

Unsurprisingly, we found that news coverage in democracies was both more voluminous and more diverse. Yet, we also found stark variation in coverage following specific types of events. Media firms in non-democracies responded to nonviolent protests by reducing coverage, while those in democracies either increased coverage or left it unchanged. For instance, following a significant increase in Libyan protests (e.g. 1st to 99th percentile), the probability that an average newspaper in a non-democracy published a story on Libya fell by 38 percent. In democracies, the same spike in protests yielded a 14 percent increase in probability of publication.

We also found differences in reporting after civilian victimization, depending on who inflicted the violence. The probability of Libya coverage in non-democracies rose by 47 percent following a spike in rebel-induced civilian deaths. Yet, media outlets in democracies typically did not change their coverage in response to rebel abuses.

Civilian victimization by government forces produced opposing patterns. Democratic states saw far more news coverage following a significant increase in civilians killed or wounded by the government, with a 15 percent uptick in the probability of a Libya story. In contrast, among non-democratic media, government killing of civilians had no effect on coverage.

A potential objection to these results is that almost every country that militarily intervened in the Libyan Civil War was a member of NATO, and hence a democracy. The tendency of media in democracies to overlook rebel crimes, while emphasizing popular protests and government atrocities, may reflect alliance commitments or rally-round-the-flag effects more than regime type.

But we found little evidence of an ‘alliance effect.’ Following almost every type of violent event, our data show no difference in coverage propensity between NATO and non-NATO democracies, or between democracies participating and not participating in the war. Although alliances may influence news coverage in important ways, military commitments did not drive the specific democratic reporting biases we identified in the Libyan case.

Democratic and non-democratic media, our research suggests, respond to the same events in very different ways. In their coverage of the Libyan Civil War, newspaper outlets in non-democracies had a distinct pro-incumbent bias, but their democratic counterparts had biases of their own, in the opposing direction. The implication is that living in a democratic state with a free press does not ensure that a media consumer will receive unfiltered information about who is doing what to whom, even during high-visibility events like the Arab Spring.

In the case of Libya, media in democracies provided ample reason for their citizens to be outraged by the regime’s mistreatment of its own people, while media in non-democracies offered their consumers similarly compelling justifications for outrage over the abuses of anti-regime rebels. To paraphrase Miles’ Law, where you stand on foreign policy questions, like the wisdom of intervening in the Libyan civil war, likely depends upon where you sit while reading the local newspaper.

Matthew A. Baum is the Marvin Kalb Professor of Global Communications and Professor of Public Policy, Harvard University.

 Yuri M. Zhukov is an Assistant Professor of Political Science and Faculty Affiliate, Center for Political Studies, Institute for Social Research, University of Michigan.