The European Commission said Wednesday that it had issued a letter of formal notice — the first step in legal action — to Poland over new disciplinary measures that can be taken against judges.
Commission Vice President Frans Timmermans said the system of oversight, introduced in 2017, appeared to "systematically subject judges to the political control of the executive."
Polish judges who have engaged in public debates or made comments about the reforms have been targeted by disciplinary officers from the government-appointed National Council of Judiciary, Timmermans said.
Judges who asked for rulings from the European Court of Justice had also had investigations launched against them.
"All this has an obvious chilling effect on the activities of judges, and this is incompatible with the requirements of judicial independence as detailed by the European Court of Justice," Timmermans said.
"The position of individual judges is at risk, with the careers and means of living being endangered for the mere fact of trying to do their jobs independently."
Timmermans said Warsaw had a chance to explain or change its mind about the law. The commission said it was acting to safeguard the rule of law in the country and that it wanted a reply to its concerns within two months.
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The move is the latest in an ongoing dispute between the EU's executive commission and the government in Warsaw, who have been at odds since 2015 over reforms introduced by Poland's national-conservative Law and Justice (PiS) party.
The government made sweeping changes to the judiciary, which were criticized by both the opposition and the EU.
Among the issues at stake was the selection process for the Supreme Judicial Council (SJC), which is responsible for naming the justices of nearly all of Poland's courts.
Equally contentious was a change to retirement provisions, with a law lowering the retirement age of Supreme Court judges from 70 to 65.
rc/jil (AFP, AP)