WARSAW, Poland (AP) — A group of pro-democracy activists in Poland entered the grounds of the country's constitutional court in an act of civil disobedience Monday, on the eve of an expected court ruling critical to the country's future relationship with the rest of the European Union.

Some stood outside with a huge banner that said “Civic Shutdown of the ex-Constitutional Tribunal.” As smoke bombs sent black plumes into the air, a smaller group made it to the court’s main entrance. They had brought boards and nails hoping to nail the door shut but did not manage to do that.

Police dragged them away as others chanted “This is not a court!”

Judges of the Constitutional Tribunal are scheduled to convene on Tuesday to decide which has primacy — Poland's own constitution or the law of the 27-member European Union.

Poland's prime minister had asked the court — dominated by ruling party loyalists — to make the judgment amid a larger conflict over systematic changes to the court system in Poland, which the EU views as a violation of democratic norms. The constitutional court's ruling was initially expected in April but has been postponed.

The activists said they do not consider the court legitimate, in part because the ruling party appointed three judges to the court soon after it won power in 2015 in a maneuver that was illegal under Polish law. Now they fear that if the court rules that Polish law has primacy over EU law, it would mark another step away from Western norms for Poland.

The country was a model of democratic transition for a quarter-century after the fall of communism in 1989. Human rights organizations say there has been democratic backsliding under the current government as it tightens control over the judiciary and media, as well as due to restrictions of reproductive rights for women and the targeting of LGBT people with harsh rhetoric.

The ruling party says its changes to the court, which have been opposed by EU institutions, are meant to fight corruption by judges and make the court system more efficient.

The justice minister, Zbigniew Ziobro, recently said the EU's criticism amounts to “hybrid warfare” against Poland.

The protesters Monday also released a long manifesto explaining their action.

“The ruthless and flagrant realization, with absolute impunity, of narrow party interests by the populists and anti-democrats currently ruling the country, which is being cynically presented as a fight for the communal interests, has reduced the Republic, over the past six years, to the rank of a geopolitical pariah and an ordinary institutional ruffian,” the statement said.