CRS on Prosecutorial Discretion in Immigration Enforcement: Legal Issues

"Regardless of whether it is characterized as “prosecutorial discretion” or “enforcement discretion,” immigration officers are generally seen as having wide latitude in determining when, how, and even whether to pursue apparent violations of the INA.  This latitude is similar to that possessed by prosecutors in the criminal law enforcement context and enforcement officials in other federal agencies." - Congressional Research Service, Jan. 17, 2013.