Adams County commissioners have rejected a permit for April’s High Times Cannabis Cup, the vast outdoor marijuana fair that coincides with the 4/20 pot celebration rally in downtown Denver.

The commissioners on Tuesday unanimously denied the Denver Mart a permit for the April 16-20 event, taking testimony from several law enforcement officials who warned that too many people sampled cannabis products openly.

“From a safety perspective, I have serious concerns about this event and this venue,” Adams County Sheriff Michael McIntosh told the commission.

The Cannabis Cup in Colorado is High Times magazine’s largest event and likely one of the biggest ticketed marijuana parties in the world.

When reached at her office in New York on Tuesday evening, High Times general counsel Cristina Buccola said she hadn’t heard about the denial and declined to speculate on the event’s future in Colorado.

Denver Mart co-owner John Doyle told the commissioners a new set of rules had been drawn up for this year to control crowd size, with a cap of 15,000 daily visitors imposed. Up to 35,000 people visited the event each day last year.

Also, the Mart would have required attendees to park in several off-site parking areas and take a shuttle to the site, at 451 E. 58th Ave., to control traffic.

But that argument didn’t hold sway. Commissioner Chaz Tedesco noted that the Denver Mart had promised it would fix problems from the inaugural 2014 Cup when it asked for a permit for last year’s event.

North Metro Drug Task Force Cmdr. Todd Reeves said during last year’s High Times Cannabis Cup a military veteran experienced breathing problems after sampling pot and a female jumped out of a moving vehicle.

He said with the hundreds of vendors expected, the total crowd at the event would be closer to 16,000 daily — exceeding the event organizer’s suggested cap of 15,000 and what fire officials have said is a safe number at the site.

Reeves also said High Times and Denver Mart had not addressed the issue of on-site public consumption of pot, which is illegal in Colorado.

John Aguilar: 303-954-1695, jaguilar@denverpost.com or @abuvthefold