It seems Janis Kuzins organized a second protest on May 13 near the Latvian Prosecutor's Office, a few hours after the chalk action. The organizer of that protest at the Cabinet of Ministers is also being charged.
The Riga Center district court will hear an administrative misdemeanor case on Monday, August 2 against Janis Kuzins, an organizer of a spontaneous protest in front of the Latvian Cabinet of Ministers (government house) against the arrest of cyberactivist Ilmars Poikans and the police search of the home of Ilze Nagla, a Latvian television reporter. She broke the story of Poikans' whistleblowing (revealing state and local government salary excesses based on State Revenue Service obtained through a security "hole" in a data base) under the name "Neo".
The protest in May was peaceful and involved up to 100 people using chalk to write protest slogans on the sidewalk in front of the government building in downtown Riga. The action was filmed by television and Nagla, one of the victims of police repression, attended the protest.
There was a second protest somewhat later at the Latvian Prosecutor's Office.
While technically illegal, the protest did no harm to property or public order and the chalk was scrubbed away in a few hours. The charges against Kuzins, who could face up to 15 days in jail or a fine of 250 lats (almost 500 USD), have been brought in an effort to put a chilling effect on spontaneous protest in Latvia.