Speaking to ETV current affairs show "Aktuaalne kaamera" Thursday night, Keres said that he thought the prosecutor's office have a suspect in mind.

"This prohibited donation is not an offense where the perpetrator is not known at the beginning of the investigation," Keres said.

"There are two sides to this crime - the benefactor and the beneficiary. In other words, if the prosecution says they don't actually have a suspect, I wouldn't believe it," he said.

Keres noted that the nature of the charge would require that Center was aware of its occurrence, to be found guilty.

The Center Party would need to know that this is a donation which may have come from a third party, and that the person identified as a donor was simply used as a mediator. Such a mediated donation is prohibited under current law and is a criminal offense. They must investigate this," he said.

As reported by ERR News, based on a crime report filed by the Political Parties financing Surveillance Committee (ERJK), prosecutors have opened a criminal proceeding to establish the origin of a €50,000 donation made to the Center Party and the motives for it.

The money had come from a little-known business person, Jana-Helen Juhaste, and media speculation has been rife about both the source of the money – according to some reports part of a settlement with her businessman ex-husband – and the motives for giving it to the ruling Center Party.

"If a party is unaware [of wrongdoing] and accepts a donation in good faith, it is doubtful that a shadow is cast. But when someone is in a situation where an individual comes to them and says I have €50,000 to give you, please take it and take it and bring it to the Center Party - no sane person should do this. He or she should know that this is a crime," Keres noted.

Keres said he assumed that the prosecutor's office opened the investigation because the amount involved, i.e. €50,000, was large enough to merit it.

The sum, on other words, attracted suspicions by both its very size and also the seemingly unusual situation of a private citizen opting to donate that amount (about three times the national average salary for a year, after tax-ed.).

"Then rumors began to spread that this particular person might not have an income that would allow him to simply make €50,000 donations to the Center Party without being a member of that party themselves, without any political views. In that sense, if it 's suspicious, the prosecution has to investigate," Keres said.

Center is in office with Isamaa and the Conservative People's Party of Estonia (EKRE). The coalition has been trying to pass a bill which would abolish the ERJK – seen by some as a move to conceal Center's finances as well as avoid paying fines of over €1 million due in the fall – but this has been filibustered by the opposition Social Democratic Party (SDE). The Riigikogu breaks for summer next week.

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