The Youth Foundation received funding from the Slot Machine Association (RAY). The current investigation aims to find out if Vanhanen should have recused himself from discussions and votes on RAY's funding of the foundation, which contributed 23,000 euros to his presidential election campaign.
According to Professor Olli Mäenpää, he and one other constitutional law expert agreed with Chancellor of Justice Jaakko Jonkka, who has already said that Vanhanen was biased.
The Constitutional Law Committee is due to hear from at least six criminal and constitutional law experts, but they have not publicly commented on their testimony.
The committee must now decide whether a crime has been committed. That would have to involve intent or negligence as well as bias.
The Constitutional Law Committee is due to hear from Vanhanen himself before it makes a decision on any potential charges. That decision is due to be announced in mid-February.