It isn’t often that Germany and Poland are united when it comes to the EU. Liberal Germany tends to be a force for closer union, while conservative Poland does its best to preserve an independent position within the bloc. Now though, the European Commission faces rebellion from both countries as it tries to re-affirm the primacy of EU over domestic law. 

The Commission last week issued a stern rebuke to Poland, after Prime Minister Mateusz Morawiecki’s government tabled a motion in March asking the country’s Constitutional Tribunal to review the constitutionality of parts of key EU treaties. One of Morawiecki’s questions raised doubts over whether EU law should have primacy over Polish law. 

In a letter to Poland, EU justice commissioner Didier Reynders said “the Commission is concerned about this motion as it contests fundamental principles of EU law, in particular the primacy of EU law”, and demanded its withdrawal. 

Polish politicians responded with fury. “This is evidence of an obnoxious, colonialist attitude towards Poland,” said justice minister Zbigniew Ziobro, who compared the EU’s attitude unfavourably with that of the Soviet Union, claiming Moscow at least “kept up the appearance” of Polish sovereignty during the communist era. Morawiecki meanwhile issued a blunt refusal, saying the process would continue “in order to once again confirm the supremacy of the Polish constitution over EU law”. 

The Polish government openly questioning the primacy of EU law would be bad enough for Brussels – but the controversy has been compounded by simultaneous legal developments in neighbouring Germany. The Commission has revisited a dispute with Germany’s highest court over a 2020 ruling which found that the ECJ had acted beyond its jurisdiction in granting the European Central Bank permission to buy member states’ debt (a policy introduced during the European debt crisis). The German court ruled that the Bundesbank – the EU’s largest central bank – should no longer participate in the scheme unless the ECB could prove bond purchases to be absolutely necessary. 

The ruling suggested the possibility for domestic legal authorities to come to their own interpretations of EU law. The failure to reverse a ruling which the Commission described as a “breach” of the primacy of Union law led the Commission to issue of a letter of formal notice last week – if the alleged breaches are left unaddressed, legal proceedings against Germany may soon be initiated. 

Simultaneous questions about the primacy of EU law – from two countries with such differing ideologies and positions within the bloc – have prompted fears that the EU is shifting away from “ever closer union” towards “Europe a-la-carte”, as a Commission spokesperson put it.  

Such a fragmentation would prove detrimental to Brussels’ new ambitions to impose “rule-of-law” sanctions on member states which fail to comply with its legal and ethical standards. Threats of such sanctions have been hanging over Poland for months now due to concerns over legal reforms which undermine the independence of the country’s judiciary. Indeed, most of the judges on the Constitutional Tribunal to which questions about the primacy of EU law have now been referred were appointed by Morawiecki’s eurosceptic government.  

MEPs are now urging the Commission to initiate rule-of-law proceedings against Poland on account of its judiciary’s lack of independence – but with that same judiciary now ruling on whether domestic or EU law should have supremacy, a major collision between Brussels and Warsaw is on the horizon. 

In this context, the Commission’s legal dispute with Germany has escalated at a particularly inopportune moment. The German court’s ruling on the primacy of domestic law makes it impossible for the bloc to present a united front against Poland – unsurprisingly, both Poland and fellow Visegrád Four rebel Hungary expressed their support for the German ruling against the ECJ. 

In challenging the role of the European courts, the Polish dispute is quickly morphing into a serious challenge to the core values underpinning the EU as a whole. The implications of a Constitutional Tribunal ruling which finds Polish law to be above EU law would be far-reaching – and potentially calamitous for Poland’s EU membership. Indeed, it is hard to see how Polish and EU law could continue to co-exist were such a ruling to be made, with both national and European legal bodies asserting their primacy over each other. 

As professor Marek Safjan, a Polish ECJ judge, said in a recent interview, “a very dangerous collision may occur between the Polish legal system and EU law. This, in turn, could threaten Poland’s place in the EU legal system.” 

Poland has cut an increasingly isolated figure within the EU of late, challenging Brussels on issues from climate change to LGBT+ rights. Yet the country’s arguments with the Commission are now shifting towards even more fundamental – and potentially irreconcilable – questions of national sovereignty. With neither side willing to back away from the conflict, serious questions about Poland’s EU membership show no sign of going away.