A special parliamentary commission in Poland is currently looking into the actions of European Council President Donald Tusk and his government’s responsibility for the Amber Gold pyramid scheme while he served as Poland’s prime minister from 2007-2014.

Amber Gold ran a pyramid scheme from 2009 to 2012 that promised high returns but ultimately cheated thousands of Poles out of €200 million in savings.

The commission has sought to determine the scope of Tusk’s authority over state security and other offices and when he was made aware of the pyramid scheme.

Tusk has denied any responsibility, pointing to the failure of the independent regulators at Poland’s Office of Competition and Consumer Protection. Investigators from the ruling Law and Justice party, Tusk’s bitter political rivals, have attempted to link Tusk to the scandal.

For his part, Tusk has said the watchdog should have prohibited or better fact-checked their advertising claims. He also said the country’s regulators failed to react in time to the warning signals about Amber Gold, which was under their authority and not the office of the prime minister.

Law and Justice’s arch-conservative party leader, Jaroslaw Kaczynski, has recently turned his efforts to trying to discredit the still-popular Tusk. Kaczynski claims that negligence under Tusk was the reason for the 2010 plane crash in which his identical twin brother, President Lech Kaczynski, was killed.