 IAACA has more than three hundred organizational members which cover nearly all law enforcement national institutions and bodies entrusted with the task of fighting against corruption and more than two thousand individual members, including prosecutors, investigators and experts with experience in anti-corruption research or practice.In 2014, Kessler became a member of the commission on appointment of the new bureau chief of the Ukrainian anti-Corruption Bureau.In 2017, Marine Le Pen filed a lawsuit against OLAF and Kessler himself, charging that the anti-fraud office acted as a tool of President of the European Parliament Martin Schulz to undermine her and her party.