Drug test

American experimentation with weed worth watching

America's experimentation with weed is worth watching. Colorado has inhaled millions of dollars in taxes during the first four months of retail marijuana sales. Meantime, red tape in Washington state has created bottlenecks as it went legit this week. Other governments pondering the chronic question of whether to legalise pot can learn valuable lessons from these experiences. A 2010 Cato study estimated that $8.7 billion in annual policing costs would disappear if all 50 states decriminalised cannabis. About the same amount in sales tax revenue would spark up, Cato argued. An analysis from the Institute for Social and Economic Research finds fuzzier economic results for England and Wales, ranging from a 461 million pound economic benefit to a 1.3 billion pound cost.

All of these projections suffer from a common problem: they rely on a slew of subjective assumptions about social behavior. That makes it tough to know which stats are skunky. Economic activity previously hidden in black markets may just become officially recorded. Some new sales may also merely substitute consumer spending on alcohol or other recreation. And health effects depend largely on the legitimised drug's eventual popularity. That's why Colorado and Washington are instructive. As the only two states to legalise grass for recreational - not just medical -purposes, they can provide tangible data. For example, the drug is proving a revenue centre for Denver, having brought in nearly $11 million in its first four months, equal to about three per cent of retail-good sales taxes. Crime fell 10 per cent year-over-year too, though cops attribute this to a change in police tactics rather than torched laws.

The Evergreen State is off to a rougher start this week, with supply shortages reported as new weed shops opened their doors. Compared to Colorado, the state took a more aggressive excise tax regime, set tougher rules and imposed caps on retail facilities and growing capacity. In this way, Washington is a better laboratory for assessing ways of regulating pot. Early outcomes in Colorado, Washington - or indeed Uruguay, the South American nation that legalised marijuana first - aren't conclusive proof of pot's promise or peril. But as these living experiments progress governments will be in a position to more accurately assess the impact on economic productivity, healthcare costs and criminal activity. Until then, stoners and non will need to hold their breath.