SIOUX FALLS, S.D. (AP) — A lawyer for the first South Dakotan charged with selling synthetic marijuana has told the state Supreme Court that the man did not know the products were illegal.

Jason Toben managed a bar in the eastern South Dakota town of Goodwin. Synthetic marijuana was sold at the bar before and after the passage of an emergency ban on many of the chemicals used to make the product.

Toben was convicted on drug charges and sentenced to nine years in prison.

The Argus Leader reports that Toben appealed, arguing the jury was improperly told he did not have to know that the product was illegal in order to be convicted.

But a state prosecutor told the Supreme Court on Tuesday that the jury instructions were proper.

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