STRASBOURG — The European Parliament plenary on Tuesday ratified the legal affairs committee’s decision to maintain the immunity of three MEPs who are being prosecuted by Hungarian authorities.

Left-wing Italian MEP Ilaria Salis, who is accused of assaulting a far-right activist in Budapest and previously served jail time in Hungary, won by a one-vote margin: 306 in favor of maintaining her immunity and 305 against.

Ahead of the vote, conservative European People’s Party chief Manfred Weber called for lawmakers to follow the Parliament’s internal rules that say lawmakers are only protected for acts while they are in office and lift her immunity.

“The reason is because the crime was committed before she became member of Parliament and the rules are crystal clear” that immunity only covers acts that have taken place during the lawmakers’ mandate, he said. “I would really ask us not to politicize any kind of these issues of lifting immunities,” Weber added.

That put Salis’ immunity in doubt as the center-right group is influential in determining majorities. But a secret ballot opened the door for some of the group’s MEPs to break ranks and vote to shield Salis from Hungary’s judicial system, which her supporters argue would deny her a fair trial in the country led by an illiberal, nationalist government.

“This vote is a victory for democracy, rule of law, and antifascism. This decision shows that resistance works,” Salis said in statement. “It proves that when elected representatives, activists, and citizens defend democratic values together, authoritarian forces can be confronted and defeated.”

Salis denies the Hungarian allegations and calls the charges politically motivated.

EPP lawmaker Markus Ferber complained his machine malfunctioned during the vote, and asked for a do-over. But Parliament President Roberta Metsola refused.

The European People’s Party’s Péter Magyar (the opposition party leader who’s currently leading Prime Minister Viktor Orbán in polling ahead of next year’s election), and the Socialists and Democrats’ Klára Dobrev (leader of the opposition Democratic Coalition), had their immunities protected by a wide margin of votes.

Hungarian authorities wanted to prosecute the MEPs on charges of theft and defamation.