The The Economic Crime Unit is responsible for the investigation and supervision of all major fraud and "white collar" crime prosecutions other than those completed by municipal authorities. The term "fraud case" applies to all cases involving financial defalcation, manipulation and other schemes of a criminal nature.

Additionally, the Economic Crimes Unit handles identity theft, mortgage frauds, election frauds, insurance frauds, frauds in the court system, jury tampering, witness tampering, extortion, threats to members of the Superior Court judiciary and violations of the Open Public Meeting Act. While the majority of the investigations conducted by the unit are self-originated, some investigations are prompted by the receipt of formal signed complaints from municipal authorities.

The Economic Crimes Unit's creation in the early 1970's was due to the obvious need to investigate "white collar" crime cases on the county rather than municipal level. Municipal police departments are often not able to thoroughly investigate complicated economic crime. Indeed, in many cases, governmental, bank, and financial records can only be obtained by grand jury subpoena, court order or search warrant, and therefore are beyond the reach of a municipal police department. Many "white collar" crimes are multi-jurisdictional in nature. Beyond this, such cases are far more complex than the "average" case. They usually require review of voluminous records by an experienced Detective.

Because of the complexity of the allegations and investigations, close interaction between the Assistant Prosecutor and Detective is necessary throughout the investigation; especially since these investigations often involve assembling and reviewing complex financial and business records, preparing and obtaining court orders for in- and out-of-state records and witnesses (such as bank records, handwriting, toll records), and frequently present witness problems involving the 5th Amendment or attorney/client privilege.

Prior to 2008, this unit was known as the Official Corruption & Economic Crimes (O.C.E.C.) Section, which was also responsible for corruption and criminal misconduct in government other than law enforcement. In 2008, these responsibilities were transferred to the Professional Standards Bureau. 

In 2009, the Economic Crime Unit completed 13 investigations and indicted 16 defendants.