Since April 1993 Stasiak had worked in the Supreme Audit Office, which was then led by Lech Kaczyński.[2] After Kaczyński won Warsaw mayoral election in November 2002, Stasiak became his deputy, being responsible for public safety and administration.[1][2]
On 19 November he again became chief of the National Security Bureau and served until 15 January 2009.[4] Then he worked as the deputy chief of the Presidential Chancellery of Lech Kaczyński,[1][2] until he was elevated to chief on 27 July 2009.[4][6]