On Sunday, a Belgian judge charged four of them, saying they are suspected of money laundering, corruption and taking part in a criminal organization on behalf of a “Gulf State.” Belgian media identified the state as Qatar, and reported that those charged included European Parliament Vice President Eva Kaili and her partner, parliamentary assistant Francesco Giorgi, as well as former member of the European Parliament, Pier Antonio Panzeri.

Others reportedly caught up in the investigation include the head of a Brussels-based union and an unnamed Italian national. European authorities have yet to confirm the implicated country, and Qatar has denied wrongdoing.

Within E.U institutions, it’s all being talked about as the biggest scandal in recent memory. Germany’s foreign minister, Annalena Baerbock, said the response will test “the credibility of Europe.”

Here’s what you need to know.

Before being charged in this case and stripped of her official positions, Eva Kaili, 44, was a Greek member and a vice president of the European Parliament.

Vice presidents can stand in for the institution’s president when needed, including chairing the monthly plenary sittings where major decisions are voted on. They also have a say in administrative, personnel and organizational questions.

But their power is limited. The European Parliament is the weakest of the three key institutions of the European Union. The institution has 14 vice presidents and 705 members.

Belgian police arrested Kaili — known in Greece as a former news anchor — and charged her with taking part in a criminal organization, money laundering and corruption, according to Agence France-Presse.

The fallout was immediate: Her political group in the European Parliament, the Progressive Alliance of Socialists and Democrats (S&D) suspended her, as did her political party in Greece, the Pasok-Movement for Change. European Parliament President Roberta Metsola suspended Kaili from her “powers, duties and tasks” as vice president on Saturday.

According to Belgian newspaper L’Echo, law enforcement officers who raided Kaili’s home on Friday found bags of cash. They also questioned Kaili’s father, after he was found with a suitcase full of cash while leaving the Sofitel hotel in Brussels. Inspectors suspect he was tipped off about the unfolding police operation, L’Echo reported, citing police sources.

Belgian prosecutors suspect “that third parties in political and/or strategic positions within the European parliament were paid large sums of money or offered substantial gifts to influence parliament’s decision.” Belgian news outlets have widely reported that the “Gulf country” suspected of being behind the scheme is Qatar, though E.U. authorities have not named it.

Kaili recently traveled to Qatar, meeting with Labor Minister Ali bin Samikh Al Marri, even though a previous trip organized for members of DMAG was postponed by Qatari officials with little advance notice, Politico reported.

Back in Brussels, according to Politico, Kaili attended a vote of the European Parliament’s justice and home affairs committee — of which she is not a member — to support a proposal to allow Qataris and Kuwaitis visa-free travel within the E.U.’s Schengen area. She also described the country as a “front-runner in labor rights” in a Nov. 21 debate.

At the conclusion of that debate, the European Parliament condemned Qatar, and soccer’s governing body, FIFA, for human rights abuses of migrant workers involved in the construction of the World Cup infrastructure. The deaths of thousands of workers remain unexplained.

The Qatari government has denied any involvement in the alleged corruption scheme, which has made news as the World Cup is in its final rounds and the country is seeking to present itself as a forward-looking and key geopolitical actor.

“The State of Qatar categorically rejects any attempts to associate it with accusations of misconduct,” the Qatari Mission to the European Union said in a tweet on Sunday. “Any association of the Qatari government with the reported claims is baseless and gravely misinformed.”

pic.twitter.com/mdxmvl8EOF

— Qatar Mission to the European Union (@QatarMissionEU) December 11, 2022

The arrests will raise fresh questions about corruption and influence-peddling in European Union institutions, putting current and former officials under scrutiny and likely leading to calls for an overhaul in institutional oversight.

In Brussels, the revelations were greeted with shock, but not surprise, with E.U. watchers and experts noting long-standing concerns about the bloc’s institutions, particularly the European Parliament.

“Whatever its final outcome, the Qatar ‘corruption’ scandal has unveiled an inconvenient, and for most Europeans already obvious, truth. Money does buy influence in the EU,” wrote Alberto Alemanno, the Jean Monnet Professor of European Union Law at HEC Paris, in an opinion piece for Politico Europe.

“While this may be the most egregious case of alleged corruption the European Parliament has seen in many years, it is not an isolated incident,” said Michiel van Hulten, Director of Transparency International EU, in a statement.

The European Parliament “has allowed a culture of impunity to develop,” thanks to lax financial rules and the absence of independent ethics oversight, van Hulten said, adding that members of the European Parliament have blocked attempts to change that. He called for the European Commission to publish its “long-delayed proposal on the creation of an independent EU ethics body, with powers of investigation and enforcement.”

Ursula von der Leyen, president of the European Commission, has called for the creation of such a body, but the official charged with making that happen has conceded that it will likely lack the ability to investigate or enforce.

On Monday, von der Leyen called the allegations against Kaili “very serious.” Josep Borrell, head of the bloc’s foreign and security arm, said they were “very worrisome.”

For now, the scandal is a gift to the E.U.’s critics, particularly leaders such as Hungary’s Victor Orban, who regularly lambaste the bloc for criticizing democratic shortcomings within E.U. countries.

On Monday morning, Orban’s Twitter account posted a meme that showed a group of men laughing hysterically with the words “And then they said the [European Parliament] is seriously concerned about corruption in Hungary” superimposed.

Kaili’s partner, Francesco Giorgi, was also charged. He was detained Friday as part of the corruption probe, and his phone was seized by Belgian law enforcement, according to Belgian newspaper Le Soir.

The European Parliament lists Giorgi as an accredited assistant to Italian MEP Andrea Cozzolino, who is part of the same parliamentary group as Kaili, and who chairs the delegation for relations with the Maghreb (Northwest African) countries. Giorgi describes himself on LinkedIn as a “policy advisor in the field of Human Rights, EU foreign affairs with an extensive network of contacts with parliamentarians, politicians, EU Institutions, NGO’s, diplomats.”

Giorgi lists himself as a founder of the Brussels-based global human-rights nonprofit Fight Impunity, whose president, Pier Antonio Panzeri, is also implicated in the corruption investigation.

Panzeri, 67, was a member of the European Parliament from 2004 to 2009 where, among other positions, he chaired the delegation for relations with the Maghreb countries (DMAG) as part of the S&D group. He founded Fight Impunity in 2019 and now serves as its president.

According to Le Soir, Belgian investigators suspect Panzeri of leading a criminal organization to influence decision-making within the European Parliament with cash and gifts on behalf of the Qatari government.

On Friday, Italian police detained Panzeri’s wife and daughter, who were the subjects of a European arrest warrant, according to Politico and the Italian newspaper Corriere della Sera.