See what's on offer inside a legal US cannabis shop

The National Black Police Association has told Newsbeat that it wants UK forces and the government to monitor cannabis legalisation in America.

Later this summer Washington will follow Colorado to become the second US state to make sales of recreational marijuana legal to over-21s.

Shy Sadis runs the medical marijuana dispensary, Starbuds, in Seattle and is hoping to soon be able to sell to recreational users.

He says buying cannabis from stores legally is much safer than getting it on the black market.

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