ST. LOUIS (AP) — A St. Louis police sergeant has filed legal action against the department, claiming its refusal to allow him to work a secondary job as a lobbyist for a pro-marijuana group violates his right to free speech.

Sgt. Gary Wiegert has lobbied on behalf of Show-Me Cannabis, which is seeking passage of a Missouri law lessening penalties for small-time marijuana possession. Police Chief Sam Dotson last week denounced the lobbying as “not what is expected of our officers.”

The department approved Wiegert’s work as a lobbyist last month, but didn’t know what he was lobbying for. The department revoked the approval Tuesday.

Show-Me Cannabis executive director John Payne calls it “viewpoint discrimination.”

Wiegert filed an injunction Wednesday asking the U.S. District Court to allow the lobbyist work to continue.

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