Last week in the Bundestag, a member of the opposition Greens party asked Maas, the foreign minister, whether the government approved of the king making policy decisions about Thailand from Germany.
"Why has the German government been tolerating for many months this extremely unusual and, in my view, illegal behavior in Germany by a foreign head of state?" asked the lawmaker, Frithjof Schmidt.
Maas responded that he was "aware of the many bizarre reports about what is happening there," but that the government's position was firm.
"We have made it clear that policies concerning Thailand should not be conducted on German soil," he said.
In an interview, a Greens member of Parliament in Bavaria, Tim Pargent, said the party's inquiries have established that the king was not in Germany as a diplomat, and is therefore bound by German laws and tax codes.
"If he likes living in Germany, that's quite clearly his right," Pargent said. "But what I want to avoid is (that) a despot who isn't treating his own people very well gets any kind of special protection here in Germany. He should be treated like everyone else."
In Thailand, where past democracy movements have been suppressed with bloody force, the government has been reluctant to use such tactics against the largely student-led protests. For months, Prime Minister Prayuth Chan-ocha said the government would consider calls to amend the constitution, but warned that the monarchy must be respected.
But many demonstrators appear to believe that Thailand's political system cannot be reformed without trimming the sails of the monarchy, which has seen its share of the public budget grow while economic inequalities worsen and the country faces a wrenching COVID-19 slowdown.
Frustration bubbled over Wednesday afternoon when the royal limousine - carrying Queen Suthida, the king's fourth wife and a former flight attendant, and his son from a previous marriage, Prince Dipangkorn - turned onto a road near Government House, the prime minister's office.
Pravit, the journalist, said about 200 protesters gathered there had not expected the motorcade to take that route. In video shot by Khaosod, one protest leader, college student Francis Bunkueanun Paothon, is seen speaking to police through a megaphone when a phalanx of black-clad officers suddenly pushed up against the crowd, clearing the road.