One-fourth of countries on CPJ's 2012 Impunity Index are in Latin America, contributing to "vast self-censorship"

Mexico, Colombia, and Brazil -- three of the 12 countries worldwide with five or more unsolved cases of journalists killed for their work -- again find themselves on the Committee to Protect Journalists' (CPJ) annual Impunity Index, released Tuesday, April 17. The Index, first published in 2008, identifies unsolved cases of journalists killed between Jan. 1, 2002, and Dec. 31, 2011. For the fifth year in a row, Iraq tops the Index, with 96 journalists' killings unsolved in the past decade.

"Deadly, unpunished violence against journalists often leads to vast self-censorship in the rest of the press corps," CPJ said.

While conditions in Colombia were found to be improving slightly, with the killings of journalists slowing and prosecutors winning some convictions, the country remains at No. 5 on the index for the second year in a row. CPJ pointed out that at least eight journalists' killings in the past decade have yet to be solved. In 2011, Colombia's Press Freedom Foundation released data showing that in the previous 34 years, 139 journalists were killed for their work, and since 1977, only five sentences were handed down against the masterminds of the crimes against journalists.

Mexico's rating deteriorated slightly, although its overall ranking remained unchanged at No. 8. In the past decade, 15 journalists' killings have gone unsolved, although that number is probably much higher, CPJ noted, as 11 other journalists have been disappeared, and numerous others have been killed under unclear circumstances. As such, "vast self-censorship has taken hold," prompting "numerous news outlets to abandon coverage of crime and corruption," CPJ said. The impunity report also highlighted that many Mexican reporters have turned to social media as a way to cover organized crime, "only to find peril there as well." For example, journalist Maria Elizabeth Macías Castro, editor of the newspaper Primera Hora, was decapitated in September, 2011, after using online social media to report anonymously on violence.

After being added back to CPJ's Impunity Index in 2011, Brazil once again made the list, with a ranking worsening from No. 12 last year to No. 11 this year. According to CPJ, five journalists' killings in the past decade remain unsolved. Despite some convictions and punishments handed down against perpetrators of crimes against journalists, "two murders in 2011 underscore the grave, ongoing risks facing provincial journalists who report on corruption, politics, and crime," CPJ said.

The release of the Index comes just as Brazil -- along with India and Pakistan, which also are on this year's Impunity Index -- blocked a United Nations plan that would have promoted journalists' safety and helped curb impunity in crimes against journalists.

Below, see CPJ's video on impunity, "Getting Away With Murder."