Federal, state and local officers arrested 42 people over three days from 22 to 24 May 2019 in one of the largest black-market marijuana enforcement actions in Colorado’s history.[1][2] Teams executed 255 search warrants in eight counties, raiding 247 homes and eight businesses and seizing more than 80,000 plants and 4,500 pounds of finished marijuana.[1][2]

The raids closed a North Metro Task Force investigation running since the summer of 2016 into cultivators growing large amounts of marijuana for illegal sale in other states.[1] The grows hid in the basements of newer houses in upscale suburban neighbourhoods, using sealed rooms, large charcoal air filters and late-night venting to hide the smell.[1] About five percent of the sites bypassed their electricity meters, cutting bills and raising fire risks.[1]

Of those arrested, 26 became state defendants and 16 federal defendants, with the federal cases carrying mandatory minimums of five to ten years.[1][2] Officers also moved to forfeit 41 homes, about 2.16 million dollars in cash, 25 vehicles and jewellery.[1] Colorado’s US attorney said the state had become the epicentre of the country’s black-market marijuana, and warned the action might be only the tip of the iceberg.[1]