CRS Reports & Analysis Legal Sidebar via FAS – Prosecution of Criminal Offenses against Congress, July 26, 2016.

“A House Oversight and Government Reform Committee hearingregarding the Federal Bureau of Investigation’s (FBI) inquiry of the potential mishandling of classified information has renewed questions about the process by which offenses against Congress are prosecuted. In the hearing, FBI Director James Comey indicated that in order for the FBI to investigate a potential incident of a witness providing false testimony under oath to a congressional committee, the FBI would need a “referral” from Congress. Chairman Jason Chaffetz sent such a referral several days after the hearing. Director Comey’s comment raises questions about the interplay between the executive branch and Congress with regard to prosecuting crimes that are intended to protect the integrity of the legislative and oversight processes. The constitutional separation of powers significantly limits Congress’s role in the enforcement of federal law. Because exercising both the power to make and enforce the law would be an apparent violation of the separation of powers, Congress may neither itself, nor through its officers, directly enforce federal law. The Supreme Court has clearly stated that “Legislative power, as distinguished from executive power, is the authority to make laws, but not to enforce them….” The Court has also suggested that “the Executive Branch has exclusive authority and absolute discretion to decide whether to prosecute a case….” Furthermore, the initiation of criminal prosecutions is within the “special province of the executive branch” and at the heart of what is known as “prosecutorial discretion.” As a result, it is generally left to the executive branch to determine when and how criminal provisions are to be enforced..”