Latin American states are dramatically altering the war on drugs - by ceasing to make war on drug users. Earlier this year, former presidents of Brazil, Mexico, and Colombia published a report calling for new policies on drugs, and now Argentina's supreme court, in a landmark decision, has ruled that it is unconstitutional to punish people for the personal consumption of marijuana. Mexico has already stopped prosecuting people for possessing small and specified amounts of a range of drugs from marijuana to heroin, and is introducing treatment instead of punishment for users. The former Brazilian president Fernando Cardoso says the war on drugs has failed.

This pioneering new approach may have been driven partly by desperation, but it is attracting worldwide attention after a long period filled with disastrous policies. The military-style crackdown on drugs in the Americas was started four decades ago by the then US President Richard Nixon, and the US’s enormous influence in Latin America meant that Latin American states as well as the UN were pressured into maintaining punitive policies above all else. As the US-driven crackdowns have toughened, smugglers and gangs have grown progressively more inventive. Dutch customs officers have found cylinders of drugs welded to ships' hulls below the waterline, and recently the Mexican navy found a tonne of cocaine in the frozen carcases of sharks aboard a container ship. Drugs have also been transported in sealed beer cans, furniture, and religious statuary. Indian traffickers have even stuffed drugs into cricket pads for export.

There is no doubting the damage that illegal drugs and the trade in them do throughout the world. The harm is not only to users in physiological terms, but also political and social. In Mexico alone, some 500,000 people are estimated to work in the drugs trade, and very senior police officers and other officials work for different gangs and cartels. In May 2009, state-level prosecutors ordered the detention of a state police chief and the relevant state’s head of security. Nearly 11,000 people have been killed in drug violence in Mexico during the last two and a half years, and even a US soldier has recently been charged with a contract killing in the Mexican drugs trade. The border between Mexico and the US state of Texas is said to be a river of drugs in one direction and a river of iron, meaning weapons, some of which are highly sophisticated, in the other. As to US countermeasures, these include the proposed use of herbicides to destroy dense cane along the Rio Grande – the border with Mexico – for better visibility and access. Critics have drawn parallels with the US use of the defoliant Agent Orange in Viet Nam, but – in a sign of the times - local elected representatives are explicit about the need to cause minimum environmental harm, and the US Environment Protection Agency confirms that the herbicide in question, Imazapyr, is reasonably certain not to cause harm to humans.

Needless to say the political issues are decisive. For a long time the United States has blamed Mexican inefficiency and corruption for the cross-border trade in drugs and weapons, but in a recent US Senate hearing there was widespread bipartisan agreement on the damage done by US inattention to drug use by Americans, whose ‘insatiable demand’ drives the Mexican drugs trade.

It is also a political matter that the new Latin American strategy does not amount to decriminalisation and is apparently being initiated as a humanitarian move which differentiates between personal use and trafficking. It will enable the release from prison of many addicts and ‘mules’ or people who carry drugs for gangs or cartels; it may also help keep drug users out of the clutches of traffickers and dealers, and it could release resources for targeting traffickers. The Argentine government does favour decriminalisation, but the Argentine supreme court, in the recent ruling, makes it clear that it is not approving decriminalisation. A number of powerful bodies, such as the Catholic Church, are very hostile to decriminalisation, and a few years ago Mexico dropped decriminalisation legislation in response to opposition in the US and fears in some quarters that Mexico would become a focus for drugs tourism.

A Brazilian judge, nevertheless, has publicly advocated that the production, supply, and consumption of all currently illegal drugs be legalised, which implies regulation, licensing, and taxation – and the elimination thereby of the worldwide illegal trade in narcotics. On the evidence, the old punitive policies are a major part of the problem; among exacerbating factors are subsidised US agricultural exports to Latin America, which make growing the coca plant the only viable economic alternative for very poor peasant farmers.

Therefore, the new Latin American approach goes further than other treatment-based policies. In 1997, the newly-elected Labour government in the United Kingdom introduced a harm-reduction policy which focused more on treatment and rehabilitation than on punishment, but one adverse tabloid headline was enough for the policy to be abandoned, with predictable consequences for almost the entire British penal system, including the imprisonment of users who need treatment and not punishment. There has also been an apparently uncontrollable increase in drug availability within prisons. In 2005, a treatment-type system called shooting-galleries was quietly introduced. Under this, heroin addicts in particular can use prescribed doses in strictly-controlled and supervised centres; early results are good but the policy still has its detractors. In contrast, Latin American governments have acted openly and courageously, and could well have given the world a lead on a truly global problem.

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