People participate in a protest at Freedom Square in Poznan, Poland. Members and supporters of opposition parties protested against changes in the judicial law and the Supreme Court | Jakub Kaczmarczyk /EPA via Getty Images Rights group calls for EU to halt Poland’s ‘authoritarian slide’ Human Rights Watch criticizes right-wing PiS government.

WARSAW — The European Union should take the strongest possible action against Poland to stop the “authoritarian slide” under the Law and Justice (PiS) government, Human Rights Watch says in a report out Tuesday.

The NGO criticizes the government, which has been in power for two years, for weakening the system of checks and balances, undermining the rule of law, and violating human rights. It said the EU should trigger Article 7, the so-called nuclear option, which can lead to a country's voting rights being suspended.

“Since it won the elections, the ruling PiS party has adopted legislation obstructing the work of the Constitutional Tribunal, enabling political interference in appointing and dismissing judges, curbing media freedom, further restricting women’s reproductive rights, and limiting freedom of assembly," the report says.

The government has also given the security service greater powers of surveillance as well as putting pressure on NGOs and violating asylum seekers’ rights, the report adds.

The PiS government has repeatedly denied those charges.

“The European Union should act to defend its values and the rights of people in Poland,” said the NGO's Lydia Gall in a statement. "The speed at which the slide has happened in Poland — just two years — is alarming."

Government spokesman Rafał Bochenek said he would not comment on the report until he had read it.

Amnesty International issued a similarly damning account of the situation in Poland last week.

Amnesty's report claimed that Polish police cracked down on anti-government demonstrators in order to “dissuade further protest.” Poland’s internal affairs ministry said the charges were groundless and the police acted to provide security and maintain public order.

For Brussels to trigger Article 7 would require the backing of all other EU member countries. Hungary has said repeatedly it will not back any sanctions against Poland.