GREENWOOD VILLAGE — They have hovered right outside windows, alarming homeowners who are opening the shades in the morning. They’ve buzzed over Fiddler’s Green Amphitheatre, capturing unauthorized concert footage while perched above thousands of unsuspecting fans.

As unmanned aerial vehicles — or drones — multiply in number, more Colorado communities are putting in place regulations to control how and where the devices are used. But crafting those rules is not easy, as cities and towns strive to balance public safety and privacy with a burgeoning consumer industry that one market research firm estimates could be worth more than $9 billion by 2024.

To further complicate things, drone regulation brings to the fore the clash between local government power and the authority of the Federal Aviation Administration, which controls airspace in the United States.

“It’s very difficult to regulate in this area because of the FAA,” Tonya Haas Davidson, city attorney for Greenwood Village, said at a study session last week . “This is their jurisdiction.”

Greenwood Village, a city of 16,000 in Arapahoe County, will nonetheless become the latest Colorado community to propose local regulations when its ordinance gets a first hearing May 7. Cherry Hills Village in 2015 was one of the first cities in the state to put in place a set of rules on drone use. Vail also forbids their use over certain parts of the mountain town.

“We want to preserve a high quality of life of all our citizens, and privacy and public safety are a big part of that,” said John Jackson, Greenwood Village’s city manager and former police chief. “But we’re not trying to be the drone police.”

Yet, that kind of policing has become reality in the city, as residents and businesses complain of drones being used in a voyeuristic manner — whether it’s peering through a bedroom window or hovering over a big-name concert at Fiddler’s Green shooting video without permission.

Last May, Jackson said Greenwood Village police and other emergency personnel had to deal with a sudden proliferation of drones flying over the scene of a fuel tanker that crashed and exploded in a giant fireball on Interstate 25.

“Suddenly, there are drones everywhere,” he said. “Why do (police) have to compete with the hobbyist who is trying to collect footage they can sell?”

Greenwood Village city councilman Tom Dougherty, an attorney who specializes in unmanned aerial vehicle law, said municipalities are trying to wrap their heads around the popular technology, both on the commercial and the recreational level, in just the past few years. Frustration toward the flying contraptions was perhaps best exemplified by a measure four years ago that would have allowed residents of Deer Trail, population 500, to shoot down drones. It was handily defeated at the ballot box.

“It’s a classic example of technology moving faster than the law,” Dougherty told his colleagues at last week’s meeting.

In an interview with The Denver Post, Dougherty said Greenwood Village is trying to “thread the needle” between protecting its residents and respecting the rights of those who own drones — with an eye toward avoiding clashes with the FAA. Such a disagreement played out in federal court last year, when a judge struck down parts of a drone ordinance passed by officials in Newton, Mass. He ruled that the city could neither set a minimum altitude of 400 feet for drone operations nor require banning drone flight beyond the visual sight line of the operator.

“(Newton’s) ordinance limits the methods of piloting a drone beyond that which the FAA has already designated, while also reaching into navigable space,” U.S. District Judge William Young wrote in his September opinion. “Intervening in the FAA’s careful regulation of aircraft safety cannot stand.”

Greenwood Village removed language from an early draft of its proposed measure that would have made it “unlawful for anyone to hover within 200 feet above the ground” because the city feared it was crossing over into airspace control issues. Instead it prepared the ordinance so as to regulate drones through existing city powers.

That would mean no recording or photographing a person via drone if that person has a “reasonable expectation of privacy”; no launching, landing or operating a drone on private property without the property owner’s consent; no use of a drone to “harass, annoy or alarm” humans or animals; and no use of the device to interfere with law enforcement operations.

Greenwood Village is exploring the idea of having the FAA declare Fiddler’s Green a no-drone zone, in the same way Coors Field and the Broncos’ stadium are off-limits to drones.

The ordinance would target drones that weigh less than 55 pounds, which are largely used by hobbyists. It’s not clear how Greenwood Village’s ordinance would affect commercial drones, such as the delivery vehicles of the future touted by Amazon and other companies.

Laura Christman, the mayor of Cherry Hills Village, said the decision by her community to clamp down on drones nearly three years ago was largely due to fears over the potential for unmanned aerial vehicles to harass the city’s prized horse population.

“For us, it’s a significant public safety issue — if a horse spooks, it could not only hurt the person on the horse, but it could run into a crowd,” Christman said.

She said that very scenario played out last year in Silverton, where a horse, apparently reacting to a low-flying drone nearby, darted into a crowd watching a skijoring race and injured three people.

Cherry Hills Village disallows the use of drones over any city streets, public parks or trails. There have been no legal challenges to the city’s regulations so far, Christman said.

“The goal here is to make them safe,” she said.

An FAA spokesman sent The Post an agency memo from December 2015 that stated that “substantial air safety issues are raised when state or local governments attempt to regulate the operation or flight of aircraft.” It said a “patchwork quilt” of varied restrictions across jurisdictions “could severely limit the flexibility of FAA in controlling the airspace and flight patterns, and ensuring safety and an efficient air traffic flow.”

But the agency said local governments do have a right to create regulations that touch on “land use, zoning, privacy and trespass.”

Kerry Garrison, the chief operating officer of the DJI Colorado authorized store, a drone retailer in Lone Tree, said he would like to see comprehensive drone regulations come out of the state legislature, so as to pre-empt the patchwork situation the FAA has warned about.

“This should be done at the state level so there’s consistency across the board,” Garrison said. “And so operators don’t have to try to learn a hundred different rules.”