Department of Investigation311Search all NYC.gov websites

DOI's Mission and History

DOI serves as the City’s independent inspector general.  Pursuant to the City Charter, DOI reports to the Mayor and the City Council, but operates independently of both.  As a law enforcement agency, DOI arrests individuals who corrupt the process and issues reports on systemic government failure.  DOI has a unique ability to carry out these functions based upon (i) its complete access to all government documents, workers and information, (ii) its ability, as part of the government, to insist upon systemic changes to the governing process, and (iii) its ability to see across all government agencies.

Founded in 1873 (as the Office of the Commissioner of Accounts) in response to the looting of city funds by Boss Tweed, DOI is one of the oldest law-enforcement agencies in the country.  Over time DOI has expanded to a staff of more than 700 attorneys and investigators, including peace officers, forensic auditors, computer forensic specialists as well as administrative personnel.  With the implementation of Local Law 70 in 2014 (requiring DOI to serve as the inspector general for the NYPD) and the completion of an MOU in 2015 to bring the Health and Hospitals Corporation under DOI’s purview, DOI now has jurisdiction over all City agencies and employees as well as any entity doing business with, or receiving funds from, the City.

DOI’s major functions include investigating and referring for criminal prosecution cases of fraud, corruption and other illegal activities by City employees, contractors and others who do business with the City.  DOI is also charged with studying agency procedures to identify systemic failures and recommending improvements in order to reduce the City’s vulnerability to corruption, fraud, waste and abuse.  In addition, DOI investigates the backgrounds of persons selected to work in decision-making or sensitive City jobs, conducts checks on those who are awarded contracts with the City and acts as the investigative arm of the Conflict of Interest Board (COIB).  

DOI’s strategy attacks corruption comprehensively through systemic investigations that lead to high-impact arrests, and recommendations that result in preventive controls and operational reforms that improve the way the City runs and delivers services to all New Yorkers.