Feds investigating former Cook County assessor, Madigan rainmaker Joe Berrios By Austin Berg 12/17/2019 The probe potentially opens up a new front in authorities’ investigation of House Speaker Mike Madigan: the property tax appeals game from which he has made millions. TAGS: capital project, Chicago, conflict of interest, Cook County, Cook County assessor, Cook County Democratic Party, corruption, Ed Burke, federal investigation, house rules, ILGA: Illinois General Assembly, Illinois, JB Pritzker, Joseph Berrios, Legislative Inspector General, legislative map, Madigan & Getzendanner, Mike Madigan, property taxes, redistricting, revolving door, Rod Blagojevich, Springfield