Marijuana Legalization Threatens These Dogs’ Collars
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Here's the issue. "Officer" Tulo is trained to sniff out marijuana and other drugs. Marijuana is now legal in Colorado. Other drugs are not. Any search of a person or car must, under the U.S. Constitution, Fourth Amendment, be based on probable cause. Court decisions have held that a dog's detection of marijuana, or for that matter explosives, gives the human police officers probable cause to make an arrest. If Tulo sniffs out marijuana, and a car and/or person is searched, the search is now, under Colorado state case law, no longer grounded on probable cause. For a similar result see Drug Alerts from Police Dogs Aren't Probable Cause for Vehicle Search, Colorado Court Rules
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I believe that this attitude shows a lack of seriousness about crime. Presumably, people who use marijuana are somewhat more likely to be involved in the "drug culture." While allowing an arrest on these may be a bit severe, allowing a search may be more within reason. I believe that ruling out canine searches based upon the drug being the "wrong drug" is a waste of canine talent, a waste of the money spent on training and worse, betrays a lack of seriousness in fighting illegal drugs.