Austria’s Constitutional Court ruled Friday that the second round of Austria’s presidential election was invalid and must be repeated.

On May 22, Alexander Van der Bellen, the former chair of the Greens, defeated Norbert Hofer (Austrian Freedom Party, FPÖ) by just 30,863 votes. The candidates of the two governing parties, the Social Democrats (SPÖ) and Austrian People’s Party (ÖVP), had been eliminated in the first round.

Van der Bellen’s victory was secured only by the counting of the 740,000 mail-in votes. Hofer held a lead after the counting of the votes. The FPÖ subsequently challenged the result due to irregularities and the challenge has been sustained by the country’s highest court.

Over the past week, 14 constitutional judges questioned 90 witnesses over five days and confirmed a number of formal mistakes. For example, the postal votes were already counted in a number of districts on Sunday, election day, even though this is only permitted to take place from 9 a.m. on Monday. In part, votes were counted without the presence of the entire electoral authority, which is a requirement.

The Constitutional Court came to the conclusion that there had been irregularities in the conducting of the postal vote with a total of 77,926 postal ballots affected.

By contrast, the court did not confirm any electoral manipulation or fraud. In many electoral districts, the FPÖ were themselves responsible for the irregularities. However, it was “insignificant if manipulations actually occurred,” the court’s ruling stated, if “the errors reach a scope capable of influencing the outcome of the election.”

Court president Gerhart Holzinger said that the ruling was aimed at strengthening trust in the rule of law and democracy. The decision did not make “anyone a winner or a loser.” Nonetheless, the FPÖ celebrated the ruling as a success. The right-wing extremist party will thus receive a second chance to gain control of the highest post in the Austrian state.

Van der Bellen’s appointment to the post of president was originally planned for July 8. The three-person presidium of the National Council, which includes FPÖ candidate Hofer, will now take over official responsibilities of the president. Hofer has already declared that he will not relinquish this responsibility during the election campaign.

Van der Bellen declared he respected the ruling of the Constitutional Court. He rejected speculation that he would not stand again for election, and declared he was sure of victory. “Of course I will stand in the re-run of the election, and I intend to win it for a second time,” he said.

The run-off is set to be repeated either on September 25 or October 2. After the decision by British voters to support Brexit, the possibility that a far right opponent of the European Union could assume the post of president in Vienna will further contribute to the crisis and destabilisation of the EU.