Quirk Forces Colorado To Waive Marijuana Taxes On Sept. 16

<p>(AP Photo/Brennan&nbsp;<span data-scayt-word="Linsley">Linsley</span>)</p>
<p>Partygoers listen to music and smoke marijuana on one of several days of the annual 4/20 marijuana festival, in Denver&#039;s downtown Civic Center Park, Saturday April 18, 2015.</p>
Photo: Smoking marijuana at 4/20 festival in Denver
Partygoers listen to music and smoke marijuana on one of several days of the annual 4/20 marijuana festival, in Denver's downtown Civic Center Park, Saturday April 18, 2015.

Colorado's unusual tax law is forcing the state to suspend taxes on recreational marijuana for one day — Sept. 16 — during which a 10 percent sales tax and 15 percent excise tax won't be collected.

The sales-tax break would shave $20 off the price of a mid-grade ounce of pot in the Denver area, where ounces this summer sell for about $200 before tax.

It's unusual for a state that has many times rejected sales-tax holidays on things like school supplies, clothing or energy-efficient appliances. Officials say it could cost the state $3 million to $4 million.

Retailers, meanwhile, are getting ready for an influx of shoppers.