Those who argue against a continuation of drug prohibition believe the current system is ineffective, costly, counterproductive, and immoral. While proponents of legalization differ as to which drugs should be legalized, how they should be controlled, and what the consequences of legalization are likely to be, they agree that drug prohibition has led to massive amounts of money spent on prosecuting drug offenders, prison overcrowding, and the diversion of law enforcement and health care resources away from other tasks. Legalization proponents argue that the historical records proves that, in a legal market, consumers prefer less potent drugs. Critics of controlled legalization believe that the history of drug use, regulation, and taxation in the U.S. demonstrates that such a scheme would perpetuate the black market in drugs by denying certain groups access to drugs, notably minors. They maintain that an effective war on drugs will erode support for drug decriminalization.