Marijuana Facts

Colorado Supreme Court rules police need probable cause before using pot-sniffing dogs to search for drugs

Colorado’s highest court ruled Monday that police using K9s trained to alert to marijuana now require more evidence about a suspected crime before they can use dogs in a search.

In a 4-3 ruling, the Colorado Supreme Court found that under the state constitution, a dog trained to alert to marijuana cannot be used before an officer establishes probable cause that a crime had been committed. Previously, officers only needed to suspect that a crime had occurred — a much lower standard.

For decades, police dogs were trained to alert to pot. But after Coloradans voted in 2012 to legalize recreational possession of small amounts of the substance, the dogs’ sniff tests in the state have become controversial because they can alert even if a person has a legal amount of marijuana.

Even before the court’s decision Monday, Colorado law enforcement agencies had begun retiring and phasing out marijuana-trained dogs in favor of K9s not trained to detect that drug.

Officers using such K9s are now subject to the same standards used for other searches of property. Law enforcement using pot-trained dogs either have to have a warrant before the sniff test or be in one of a handful of situations outlined by state law that allows police to complete a search without a warrant.

The decision could have national implications as other states continue to legalize marijuana, experts previously said.

“To the extent we end up alone on a jurisprudential island, it is an island on which Colorado voters have deposited us,” Supreme Court Justice William Hood wrote in the majority’s decision. “Our role is not to question their decision. Rather, it is to apply the logic of existing law to a changing world. Though we are the first court to opine on whether the sniff of a dog trained to detect marijuana in addition to other substances is a search under a state constitution in a state that has legalized marijuana, we probably won’t be the last.”

Three of the court’s seven judges disagreed with the majority’s findings and questioned how the decision meshed with federal law and the U.S. Constitution.

This is a developing story that will be updated.