Several senior leaders of the right of centre Popular Party (PP), including Prime Minister Mariano Rajoy, are suspected of receiving "additional pay" of up to €15,000 per month from the former party treasurer, Luis Bárcenas. Rajoy and other PP officials have denied the allegations.
Bárcenas is being investigated as part of a criminal investigation into secret PP funding between 1990 and 2008. The payments consisted mainly of commissions received from construction companies, which thrived during the housing market boom of the 2000s.
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