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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 our investigations. The City Charter and various Executive Orders, which can be found here, empower DOI to carry out its mission, including giving it access to City documents, workers and information; the power to subpoena documents and take testimony under oath; and the breadth of scope to see across all City agencies, enabling DOI to root out systemic problems.

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. DOI’s staff consists of Inspectors General, investigators, attorneys, forensic auditors, computer forensic specialists and administrative personnel. The agency continues to adapt and grow to respond to current needs of the City. For example, in 2014, with the implementation of Local Law 70, DOI created the Office of the Inspector General for the NYPD and, in 2015, through a Memorandum of Understanding, DOI established the Inspector General Office overseeing New York City Health + Hospitals.

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. As part of its investigations, DOI identifies systemic corruption vulnerabilities and recommends improvements to reduce the City’s exposure to corruption, fraud, waste and abuse, and improve the function of City agencies. In addition, DOI investigates the backgrounds of City workers who earn more than $100,000 annually and those selected to work in sensitive City jobs; conducts checks on companies who are awarded contracts with the City of $250,000 or more; and acts as the investigative arm of the Conflicts of Interest Board (COIB).

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