As the sun set over Bangkok in late March, a Thai graffiti artist walked up to the pearl-white walls of the 18th-century Grand Palace and spray-painted an anarchy symbol along with the numbers "112” crossed out, like a No Smoking sign.

Within minutes, police tackled Suttawee Soikham, 25, and pinned him to the ground. Although he was only hit with charges related to public vandalism that night, he was arrested days later over an old Facebook post for breaching Article 112, a law known as "lese majeste” that can put offenders behind bars for as many as 15 years if they’re convicted of insulting the king or several other top royals — the very statute he was protesting.

Then something happened that would’ve been unthinkable just a few years ago: Footage of the scene went viral on social media, prompting copycat graffiti to pop up at bus stops, taxi stands and Skytrain stations across the capital.