Two years ago, Africa reached a milestone in neighborly concern. A special court set up by the 54-nation African Union convicted a former dictator in Chad of crimes against humanity. Now many countries in Latin America want to do something similar, all in the name of regional solidarity for democracy and rule of law.

On Sept. 25, Mexico, Brazil, Argentina, Chile, Peru, and Paraguay agreed to ask the International Criminal Court (ICC) to investigate crimes against humanity in Venezuela. Together the six countries represent about three-quarters of Latin America’s population.

Their request is an easy call. Several human-rights bodies have already documented the impunity of Venezuelan officials under President Nicolás Maduro in the killing of hundreds of protesters and political dissidents since 2014. Amnesty International, for example, found 22 percent of homicides committed in 2016 were by government security officers. And Mr. Maduro’s harsh rule and high-level corruption have also led to mass hunger and the exodus of more than 7 percent of the population to surrounding nations. A new poll found 20.5 percent of Venezuelans would leave the country if Maduro stays in power and the economy does not improve.

The request by the six countries to seek ICC prosecution is unprecedented on the world stage. It adds to the steady ratcheting up of financial sanctions on the Maduro regime by various nations, such as the United States. While the ICC has not indicated if it will act, the request nonetheless signifies the urgency of the ongoing refugee crisis – which is reaching Syrian proportions – and the need to prevent Venezuela from imploding into more violence.

The official crimes in Venezuela are no longer an internal matter. Latin America’s democracies cannot allow their most desperate neighbor to become a scene of mass atrocities, tarnishing the image of the region. Indifference is no longer an option. Being neighborly is, even if it means using the long arm of the law across borders to save Venezuela.