BOSTON (AP) _ Police can't pull over drivers just because they detect the smell of marijuana coming from their car.

The state's highest court issued the ruling Tuesday in the case of a New Bedford police officer who pulled over a driver in 2012 based on the odor of marijuana coming from the car and without witnessing any traffic violation.

The Supreme Judicial Court pointed to a 2008 ballot question approved by Massachusetts voters that decriminalized possession of one ounce or less of marijuana.

The court argued that because of the new law, the smell of unburnt marijuana no longer constitutes probable cause to believe that a criminal amount of the drug is present.

The court said allowing such stops encourages police to continue investigating individuals suspected of possessing marijuana in the same manner as before decriminalization.

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