In a recent report by the Rand Corporation titled Securing Tyrants or Fostering Reform?: U.S. Internal Security Assistance to Repressive and Transitioning Regimes, the research institution studied US support to El Salvador's internal security forces following the civil war. The following is the summary of their conclusions:
In El Salvador, U.S. assistance improved the accountability and human rights practices of the Salvadoran police but did not improve the effectiveness of Salvadoran security forces, as the rate of violent crimes soared. The U.S. Department of Justice and the U.S. military played a critical role in helping dissolve the three military-controlled internal security forces that had reputations for human rights abuses: the National Guard, the Treasury Police, and the National Police. A single new police force, the National Civilian Police, was created, which established a doctrine that emphasized human rights and civilian leadership. U.S. success was possible because of some leadership buy-in on the part of Salvadoran political leaders, institutional development, and pressure from the United States, the United Nations (UN), and other governments. However, the significant decline in torture and extrajudicial assassinations was accompanied by a major increase in crime rates, including the rate of violent crime, which the local police were unable to stem. The failure to improve the effectiveness of the Salvadoran police demonstrates that human rights and effectiveness must go hand in hand. Both are critical in establishing a viable police and internal security force.