Page 16 of 42 103 Minn. L. Rev. 844, *875 The mandatory prosecution duty, known as the "legality principle," is itself a safeguard against selective underenforcement due to bias or favoritism. It is primarily an anti-discrimination injunction, intended to ensure that prosecutors treat like cases alike, rather than a mandate to ensure public safety and order through full enforcement. !°° Administrative and judicial enforceability of that duty is intended to ensure its effectiveness. 2. Oversight of Declination Decisions in England and Wales The United Kingdom was an E.U. member state when the victim's right Directive was issued, !°° and its largest criminal [*876] justice system - the combined jurisdictions of England and Wales - provides several grounds on which victims or other aggrieved parties may obtain both administrative and judicial review of non-prosecution decisions. Yet the reasons for this relate foremost to public rather than private interests: "a decision not to prosecute, especially in circumstances where it is believed or asserted that the decision is or may be erroneous, can affect public confidence in the integrity and competence of the criminal justice system." 107 In line with other E.U. member states, English victims can seek administrative review within the Crown Prosecution Service. The process appears to be meaningful; in recent years, between seven and thirteen percent of prosecution decisions challenged in this way have been reversed. !°8 Moreover, noncharging decisions are also subject to judicial review - a policy rarely seen in other common law jurisdictions. !°? The standard is deferential, but English courts do periodically overturn non-prosecution decisions after evaluating them against written standards in the Code for Crown Prosecutors and other guidelines. !!° English courts have disapproved of decisions not to prosecute upon finding they were based on an unlawful policy !!! or were found to be [*877] "perverse" under a general