On Monday, a suspect faced federal charges in a Dallas County court for allegedly sending a strobing GIF that triggered a seizure in Kurt Eichenwald, a Newsweek writer with epilepsy, late last year.
Light-induced seizures have been fought with lawsuits and TV bans in the past. But like something out of Black Mirror, they've had their day in what's likely the first criminal trial over a seizure induced via the internet.
The case has similarities with previous complaints over videos, often with bright flashing lights, that triggered seizures. For example, a scene from a 1997 episode of Pokémon, in which Pikachu launches a lightning attack, reportedly hospitalized some 685 children.
Eichenwald, who has been vocal about his epilepsy in the past, allegedly suffered an eight-minute seizure in December after opening a tweet containing the flashing GIF and a message that read: "you deserve a seizure for your posts." Eichenwald's wife found him and called 911. The FBI later arrested one John Rivello, who has been charged with cyberstalking and aggravated assault with a deadly weapon.
"The implications I think are very simple, that several law enforcement authorities will not tolerate people attacking journalists even if they're using new technological tools like a Twitter message," Eichenwald's lawyer, Steven Lieberman, told Motherboard.
Read more: So How Exactly Does a GIF Cause a Seizure?
Cases like this have strong implications for the roughly 10,000 people with photosensitive epilepsy in the US. For this small percentage of the 2.7 million total Americans who suffer epilepsy, innocent-seeming everyday activities can pose a danger.
"There are potential environmental threats everywhere: theaters, dance clubs, rock concerts, the Internet, the street and at home," warns the nonprofit Epilepsy Foundation. Certain light colors and speeds may be more harmful than others.
Lawsuits have plagued video game creators since at least 1991, when Douglas L. Webster, a Michigan lawyer, sued Nintendo after a 15-year-old girl had a seizure. And in 2004, Nintendo was accused of knowing that its games caused seizures.
Eichenwald's case has been met with some skepticism, given the journalist's track record of somewhat misleading reporting. Some have questioned why his wife would take the time to tweet as her husband was having a seizure.
Part of the doubt may come from sheer surprise that just a GIF could put someone in danger. Though counterintuitive, studies have chronicled light's effect on this small portion of those with epilepsy.
Eichenwald's case has less to do with expression and more to do with any physical harm he suffered.
"This doesn't even get in the door of the First Amendment," Danielle Citron, a legal scholar at the University of Maryland, told the Washington Post. "It doesn't have expressive value… It doesn't express someone's autonomy of views and opinions."
The video, to the prosecution, was far from accidental. "It's very clear that he knew he had epilepsy," Lieberman said. "Here they saw a special vulnerability and they exploited it."
Videos like the one that Rivello allegedly sent Eichenwald are easy to find on the internet; Eichenwald claimed that he had been sent at least 40 last year.
In 2008, the Epilepsy Foundation had to shut down a forum after trolls posted seizure-inducing imagery. RyAnne Fultz, who suffers from a type of epilepsy that is triggered by patterns, clicked the wrong link. Bright flashing colors filled the screen. "It was a spike of pain in my head," she told Wired at the time. "And the lockup, that only happens with really bad ones. I don't think I've had a seizure like that in about a year," she said.
Some countries have made special protections. Eighteen people reported seizures from an animation of the 2012 London Olympics logo, prompting the United Kingdom to adopt television guidelines. Japan created similar guidelines following the Pokemon incident.
On Monday, a grand jury referral increased Rivello's charges, accusing him of assault with "a deadly weapon, to wit: a tweet and a graphics interchange format (GIF) and an electronic device and hands during the commission of the assault."
Editor's Note: Here is a tool to test your GIF for sensitivity.