Both paid-for and infotainment messages appear on screens inside Riga's minibuses, run by Rigas Mikroautobusu Satiksme, a contractor for the municipal Rigas Satiksme company.
A storm broke out after a 'day in history' announcement in Russian and Latvian on Riga minibuses claiming that, in the course of world war two, Nazi Germany had taken the Klaipēda region from Lithuania on March 22, 1939.
Historian Edgars Engīzers was quick to point out that the second world war had in fact started on September 1, 1939 when Britain and France declared war on Germany following the invasion of Poland. He claimed that Rīga's local authorities might be trying to shift people's views over who's to blame for the war to a Kremlin-friendly narrative.
"Was that done with a goal of reducing the role of the Molotov - Ribbentrop Pact in starting the war? Or with the goal of putting away the USSR invasion of Poland on September 17 away from the start of the war...?" he wrote in a letter to the lawmakers.
The Saeima committee on May 10 debated whether the messages should be considered advertisement or mass media, and consequently what laws should apply in this case.
Lawmakers admitted that they cannot adapt laws regarding emerging technologies quickly enough.
Meanwhile Culture Ministry representative Aiga Grišāne told MPs that media law amendments are upcoming and that the responsibility about the content lies on the author's hands, but censorship is forbidden.
"The Culture Ministry has started work on a new legal regulation for media where we'll be taking new platforms and ways of content integration into account. Social media and responsibility is another matter. Currently the law of a democratic country doesn't allow restricting content," she said.
The Culture Ministry is to present the new amendments by fall 2017.