DENVER, Colo. (Legal Newsline)-Medical marijuana dispensaries in Colorado are subject to collecting sales taxes, state Attorney General John Suthers said in a formal legal opinion issued Monday.

The Republican attorney general's opinion came amid confusion over whether medical marijuana could be taxed since it is against federal law but allowed in Colorado under the state's voter-approved Amendment 20, which passed in 2000.

In response to a query from Gov. Bill Ritter's office, Suthers said medical marijuana is "tangible property," able to be taxed by the state. He said only seeds would be exempt from sales tax.

"Colorado law is clear: Medical marijuana, in most instances, should be subject to state and local sales taxes," wrote Suthers, a former U.S. attorney. "This formal opinion should help clear up many of the uncertainties surrounding the taxation of medical marijuana."

Prescription drugs are exempt from taxation under Colorado law. But because medical marijuana is not a drug regulated by the U.S. Food and Drug Administration, it isn't prescribed, and therefore, does not fall under the exemption.

In Denver, City Councilman Charlie Brown wants to charge medical marijuana dispensaries a 3.62 percent sales tax.

The U.S. Department of Justice recently announced that users and providers of medical pot won't be prosecuted by federal officials so long as they comply with state laws governing medical marijuana.

From Legal Newsline: Reach staff reporter Chris Rizo at chrisrizo@legalnewsline.com.