DENVER -- Colorado Gov. Bill Ritter is telling medical marijuana dispensaries to start paying sales tax -- and the budding industry is ready to pay for "legitimacy."

Ritter's move comes after Colorado Attorney John Suthers concluded in an opinion issued Monday that medical marijuana is considered personal property that can be taxed and shouldn't be treated like prescription drugs, which are tax-exempt.

"A number of dispensaries are already paying taxes and based on this opinion all should be paying," said Evan Dreyer, spokesman for the governor, who requested the attorney general's opinion.

Leaders of the booming medical pot business said they're eager to embrace taxation and shed the stigma of being "shady characters," if it brings some tolerance from wary state and local officials.

"If taxation is a way to get over that stigma, I think it's worth it," said Courtney Tanning, executive director of the Colorado Wellness Association, a new alliance of medical marijuana dispensaries "committed to creating a fair and ethical regulatory framework" for the industry, according to its Web site.

"If contributing to the state is what gets us taken seriously, I think people are prepared," Tanning added.

As cash-strapped state and local governments scrape for new revenue sources, Tanning said she hopes a medical pot tax windfall will slow the spread of local moratoriums against new dispensaries and law enforcement drug raids.

"We're a really good source of money and, frankly, there really aren't many other (tax revenue) sources are around right now. Budgets are being cut everywhere. There's libraries closing," she said.

"It's a black market that's been there for decades. It's just untouched," Tanning added. "So if we just bring it into the light, I really think it would be so beneficial to the statewide community."

The Colorado Department of Revenue said it will soon be mailing letters telling pot dispensaries to pay their sales taxes.

"To the extent that we know where these folks are, we will be sending letters informing them of the requirement to pay taxes," said Mark Couch, spokesman for the Department of Revenue. "It's always been our position that it was subject to sales tax."

Suthers' opinion said only seeds would be exempt from sales tax in Colorado. Otherwise, it would be up to vendors to collect and remit sales tax on other forms.

"Colorado law is clear: Medical marijuana, in most instances, should be subject to state and local sales taxes," Suthers said. "This formal opinion should help clear up many of the uncertainties surrounding the taxation of medical marijuana. Many other questions surrounding medical marijuana and Amendment 20 to the Colorado Constitution will have to be resolved by the courts or the Colorado Legislature."

Suthers said medical marijuana is considered personal property that can be taxed. He says it doesn't qualify as a prescription drug that would be tax exempt, and it doesn't generally qualify for agricultural tax exemptions. Retailers must have a state retail sales license, according to Suthers.

The State of Colorado planned an immediate tax on medical marijuana, as a result of the opinion.

It wasn't immediately clear how much revenue the change would generate in the cash-strapped state.

The city of Denver plans to impose its own sales tax on medical marijuana.

City Attorney David Fine told The Denver Post that the city will notify dispensaries it plans to collect municipal sales tax on medical marijuana starting next month.

An amendment approved by Colorado voters in 2000 allows marijuana use for "debilitating medical conditions," but marijuana remains illegal under federal law.