A German court is due to rule this week on whether security services can treat the far-right Alternative for Germany, or AfD, and its youth wing as suspected extremist organizations, a decision that could cost the party dearly in upcoming European elections.

If the higher administrative court in Muenster confirms a lower court finding, the Federal Office for the Protection of the Constitution, or BfV, tasked with scrutinizing threats to Germany’s constitutional order, will retain the power to deploy the full range of intelligence tools against the party.

They could be anything from tapping phones to recruiting informants inside a party whose leaders have dismissed citizens of foreign ethnic backgrounds as “passport Germans” or complained about “fecund Africans” flooding Germany.

The party, which has 78 of the 736 seats in the Bundestag, the German federal parliament, maintains that it is a democratic, non-extremist formation. Regional branches of the party have already been formally declared extremist threats.

The case’s title “AfD versus Federal Republic of Germany” hints at its significance for a country that has built its post-war reputation building a model democracy with strong safeguards against extremism now seeing a far-right party polling as much of a third of the vote in some regions.

A finding that it is suspected extremist could hurt the party in western Germany, where it is less well established, and voters are traditionally more cautious about parties that are labeled extremist.

It could also complicate dealmaking on a European level: potential partners, including France’s Marine Le Pen, have warned that overt racism could make it hard for her National Rally party to work with them.

The BfV first began treating the party as a possible extremist organization in 2021. A lower court rejected the AfD’s appeal against the move the following year.

The court in Muenster, in whose jurisdiction the BfV’s headquarters in Cologne lies, is expected to issue a definitive ruling on the facts on Tuesday after two days of hearings.

The party is now polling in first place in several of the poorer, post-industrial eastern states where its anti-establishment, anti-immigration message is particularly resonant.

But the party has also faced mounting pressure, especially after the revelation that senior figures had attended a meeting where the “remigration” of “unintegrated” German citizens was discussed — widely seen as code for the expulsion of people of non-ethnic-German descent.

That triggered weeks of street protests and even statements of concern from titans of German corporate life, normally exceptionally reticent on matters of daily politics.

The party has slipped in the polls slightly, though it remains second with around 19% support, behind the opposition conservatives but well ahead of Chancellor Olaf Scholz’s Social Democrats with 15%.