The president of the European Commission has said that she is “deeply concerned” by a Polish court ruling that parts of EU treaties are incompatible with the Polish constitution.

Ursula von der Leyen has told the commission's services to analyse the ruling, made by Poland’s Constitutional Tribunal, “thoroughly and swiftly”, before a decision is made on the next steps.

Poland's Prime Minister Mateusz Morawiecki had asked the court to rule on whether the EU could prevent his government from implementing changes in the judicial system that are opposed by the EU.

In its ruling, the Constitutional Tribunal said that it had a right not only to check the constitutionality of EU law, but also the rulings of the CJEU.

Treaties ‘very clear’

Von der Leyen said that the EU treaties made it “very clear” that all rulings by the CJEU were binding on all member states' authorities – including national courts.

“This is what all EU member states have signed up to as members of the European Union,” she said.

“We will use all the powers that we have under the treaties to ensure this,” the commission president concluded.

Independence

Poland’s changes to its judicial system have been widely interpreted as compromising the independence of the country’s courts, because they introduce a disciplinary chamber with the power to punish judges for their rulings.

The CJEU has ruled that the changes are in breach of EU law.

Early in 2020, Supreme Court Justice John McMenamin and other legal professionals marched in support of the Polish judiciary, and handed in a letter of support from outgoing Chief Justice Frank Clarke and the Association of Judges in Ireland (AJI).