The protesters, including members of the so-called Border Defence Movement and pro-opposition groups known as Gazeta Polska clubs, tried to block the entrance, while officers dismantled barriers previously set up by demonstrators.
Those present included Robert Bąkiewicz, leader of the Border Defence Movement, Tomasz Sakiewicz, editor-in-chief of Republika television, and Law and Justice (PiS) MPs, including Antoni Macierewicz, state news agency PAP reported.
Warsaw police said officers were not taking action against the tribunal or its independence.
They denied reports that police were storming the building, saying their actions were being carried out openly in front of television cameras and journalists.
On Wednesday morning, Berek, elected by lawmakers last month as a Constitutional Tribunal judge, took his oath in parliament in the presence of lower-house Speaker Włodzimierz Czarzasty and upper-house Speaker Małgorzata Kidawa-Błońska.
The oath included the phrase "before the president," although Nawrocki did not attend.
After the ceremony, Berek submitted the oath in writing to the President's Office, with his signature notarised. He then travelled to the tribunal with other judges.
Czarzasty said parliament's role was over and that the tribunal should now begin operating effectively.
He argued that an oath could be taken without the president’s physical presence if the essential elements of the procedure were preserved, including the required wording, verification that the oath had been taken, and its submission to the president.
After 10 a.m., police stationed at the tribunal's entrance allowed Berek and several other judges elected by the current parliament to enter the court.
More to follow
(sp/gs)
Source: PAP