A survivor of the shooting at Al Noor mosque in Christchurch, New Zealand, waits for his wife to pick him up.Kai Schwoerer / Getty

By the time the news of mass shootings at two mosques in Christchurch, New Zealand, spread around the world, the effort to remove materials left behind by a suspect in the terror attack online was already well under way.

Social-media sites including Facebook, Twitter, and YouTube said they were removing footage of the attack, which was broadcast live to Facebook, from their platforms. Accounts associated with the suspected perpetrators were suspended, and copies of a 74-page manifesto posted by one of the suspects were taken down. New Zealand police urged the public not to share the content.

But these materials were still readily available in one corner of the internet: the British press. The Daily Mail and the Daily Mirror, which are among the most popular newspapers in the United Kingdom, published edited versions of the video to their websites. The Sun, the U.K.’s most widely read newspaper, ran a GIF from the video on its homepage. The Mail even hosted the suspect’s full manifesto, which was available for download directly from its website.

Only after backlash did the newspapers remove the content from their websites. Lloyd Embley, the group editor in chief of the Mirror, confirmed in a statement that the video was uploaded in violation of the newspaper’s policies. A spokesperson for the Mail said that publishing the manifesto to its website was done “in error.”

Such atrocities invariably raise questions about how news organizations should cover acts of violence. When, for example, is it appropriate to label an event an act of terrorism or someone a terrorist? How should journalists frame their stories? When should the media publish the names of the perpetrators involved in attacks, if at all? The attacks in Christchurch have raised another such question: Should media outlets share details of an attack, including related images and propaganda, with their audience? And what are the implications for the public discourse if they do?

We asked Al Tompkins, a senior faculty member at the Poynter Institute, the nonprofit journalism school in St. Petersburg, Florida, about what news organizations should do in such cases. “My suggestion is not to have an outright prohibition against using graphic images, but I would raise my bar pretty high to say this: Is there any reason why the public needs to see these images in order to understand what occurred?” he said.

Tompkins suggested that in the case of an incident such as a police shooting in which the facts are in dispute, the release of graphic video might be justified. But in a case such as the attacks in Christchurch, he said, “the video [is] not illuminating beyond the description of what occurred.”

Tompkins said the same rules should govern a shooter’s manifesto. It is usually acceptable to provide a generic summary of the manifesto, he said, but citing the example of the Unabomber’s manifesto—published by American media in 1995, following an appeal from federal law-enforcement agencies that wanted to avoid more casualties—he added: “Rarely, under the most extreme circumstances, would such a thing be re-publishable.”

Publishing terrorists’ manifestos “tend[s] to do two things,” he said. “First, it gives more power to the shooter; second, it does nothing to illuminate anything that we don’t already know.”

In the long term, exposure to such events inures the public to its impact. Indeed, in the United States, which has seen hundreds of mass shootings over the past few decades, gun sales typically rise in the immediate aftermath, perhaps in fear that lawmakers might enact gun-control legislation. In fact, social scientists have long postulated that the media’s coverage of mass shootings might contribute to more mass shootings. A recent discussion paper by the economists Michael Jetter, a senior lecturer at the University of Western Australia, and Jay K. Walker, an assistant professor at Old Dominion University, in Virginia, found a link between media coverage of mass shootings and subsequent mass shootings over the next 10 to 14 days.

Yet these latest shootings also illustrate a difficulty in policing such coverage. Though the attacks occurred in Christchurch, the offending stories were published by British outlets, and were free to read the world over. The New Zealand police might have called for caution when circulating the details, but their jurisdiction does not extend across the internet.

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