CORRECTIV has conducted an investigation on 400 mutual banks in Germany. Where are their problems, what are their difficulties, what are their challenges. To get the tasks done, they involved more than 600 citizens in a crowdsourcing project, with success. Together citizens and reporters were able to analyse all business reports, extract relevant information and secure reliable data. David will explain, how to use this kind of investigative crowdsourcing – where are its chances and risks.