New York City Department of Investigation

DOI is one of the oldest law-enforcement agencies in the country, formed in the 1870s following a scandal in which the corrupt William “Boss” Tweed and his unscrupulous cronies skimmed millions from the City coffers. The agency investigates and refers for prosecution City employees and contractors engaged in corrupt or fraudulent activities or unethical conduct. Investigations may involve any agency, officer, elected official or employee of the City, as well as those who do business with or receive benefits from the City.