Special Counsels, Independent Counsels, and Special Prosecutors: Options for Independent Executive Investigations [June 1, 2017] [open pdf - 661KB]
"Under the Constitution, Congress has no direct role in federal law enforcement and its ability to initiate appointments of any prosecutors to address alleged wrongdoings by executive officials is limited. While Congress retains broad oversight and investigatory powers under Article I of the Constitution, criminal investigations and prosecutions have generally been viewed as a core executive function and a responsibility of the executive branch. Historically, however, because of the potential conflicts of interest that may arise when the executive branch investigates itself (e.g., the Watergate investigation), there have been calls for an independently led inquiry to determine whether officials have violated criminal law. In response, Congress and the U.S. Department of Justice (DOJ) have used both statutory and regulatory mechanisms to establish a process for such inquiries. These responses have attempted, in different ways, to balance the competing goals of independence and accountability with respect to inquiries of executive branch officials. [...] Ultimately, under the previous statutory authorization for independent counsel appointments or under the existing regulatory authority to appoint special counsels, the Attorney General holds the sole authority to initiate the appointment for such investigations and prosecutions. However, other alternatives of investigation and oversight of actions by federal officials--whose methods are beyond the scope of this report--are available, such as inspector general investigations and congressional oversight investigations."
CRS Report for Congress, R44857
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html