Wąsik also served as a member of the Sejm, representing the constituency of Płock, from 12 November 2015 until 20 December 2023, when his mandate expired due to his being sentenced to prison for an intentional crime.[7][6][8]
Wąsik co-founded Poland's Central Anticorruption Bureau, where he served as the deputy head from 2006 to 2009, under head Mariusz Kamiński.[9][10] In 2009, Wąsik and Kamiński were accused of abusing their power by allowing subordinates to use entrapment when investigating a political opponent, Andrzej Lepper, who later killed himself.[11][12]
The two were found guilty in 2015 and sentenced to three years in prison, but were pardoned by President Andrzej Duda a few months later, before their appeal was decided.[9][12] Legal experts questioned whether the pardon was valid if it was granted before all possible avenues of appeal were exhausted, and the Supreme Court overturned the pardon on 6 June 2023.[13][14]