Research Institute, a branch of the RAND Corporation and released in 1988. The study noted that seven previous studies in the past nine years, including ones by the Center for Naval Research and the Office of Technology Assessment, had come to similar conclusions. Interdiction efforts, using current armed forces resources, would have almost no effect on cocaine importation into the United States, the report concluded. During the early to mid-1990s, the Clinton administration ordered and funded a major cocaine policy study again by RAND. The Rand Drug Policy Research Center study concluded that $3 billion should be switched from federal and local law enforcement to treatment. The report said that treatment is the cheapest way to cut drug use. President Clinton's Director of National Drug Control Policy rejected slashing law enforcement spending. Plan Colombia itself didn't exist at the time of the second RAND study, but the U.S. aid package has been criticized as a manifestation of the predominant law enforcement approach to the drug trade as a whole. Guerrillas and oil Critics of Plan Colombia, such as authors Doug Stokes and Francisco Ramirez Cuellar, argue that the main intent of the program is not drug eradication but to fight leftist guerrillas. They argue that these Colombian peasants are also a target because they are calling for social reform and hindering international plans to exploit Colombia's valuable resources, including oil and other natural resources. As of 2004, Colombia is the fifteenth largest supplier of oil to the United States and could potentially rise in that ranking if petroleum extraction could be conducted in a more secure environment. From 1986 to 1997 there were nearly of crude oil spilled in pipeline attacks. Damage and lost revenue were estimated at $1.5 billion, while the oil spills seriously damaged the ecology. While the assistance is defined as counternarcotics assistance, critics such as filmmaker Gerard Ungeman argues it will be used primarily against the FARC. Supporters of the Plan such as the U.S. embassy in Bogotá and U.S. Under Secretary of State for Political Affairs Marc Grossman argue that the distinction between guerrillas, paramilitaries and drug dealers may have increasingly become irrelevant, seeing as they could be considered as part of the same productive chain. As a result, counternarcotics assistance and equipment should also be available for use against any of these irregular armed groups when necessary. Human rights conditions In June 2000, Amnesty