J.C. Buehler was 3,000 feet above an Indiana farm field when he saw the drone. It didn’t appear on his single-propeller airplane's systems, and he almost didn’t see it about 1,000 feet away.

Buehler was working as a Federal Aviation Administration examiner certifying a new pilot, who noticed the drone first. Neither knew what it was doing or whether it was legal.

“It was a little scary to see a drone very close to an aircraft into which I was strapped,” Buehler told the Washington Examiner.

To address the increasingly common sight, Congress included in this year’s FAA Reauthorization Act permission for the Department of Homeland Security to “track,” “disrupt,” “control,” and “seize or otherwise confiscate” drones deemed a “threat."

Civil liberties groups are concerned, however, that authorities could misuse the authority to surveil aircraft, silence journalists, and flout traditional standards for confiscating property.

President Trump signed the bill into law this month after it passed with little discussion — just one Senate hearing and no House debate. The term “threat” is undefined, and no specific process is outlined for the return of seized drones.

“This bill gives DHS and DOJ that authority to seize privately owned drones, and there’s no mechanism in the bill for people to reclaim their property and prove they were just taking pictures of pelicans in the ocean,” said India McKinney, a legislative analyst at the Electronic Frontier Foundation, which campaigned against the bill.

McKinney said there are legitimate concerns about surveillance, including whether data would be stored or kept forever, and that "whether or not [authorities] will be doing it has no impact on whether you should be allowed to do it under the law.”

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The new law is the latest development in the federal government's approach to drones, which over the past decade morphed from specialized weapons of war into a diverse category of aircraft used to survey farmland and amuse children as toys.

The first major tranche of federal rules came in 2016. Now, civilian drone pilots need to register aircraft over 0.55 pounds. Recreational drones can’t fly above 400 feet, in restricted airspace, or near airports. Commercial drone pilots need licenses.

Buehler, who worked 20 years as a commercial airline pilot before teaching aviation law at Indiana University, said many people don’t bother to learn or abide by the rules after they buy a $100 drone from Wal-Mart.

Buehler said he collided with three birds as a pilot, whose flesh and bone can cause substantial damage. With a 10-pound metal drone, “the physics are a lot less forgiving when the two things come together,” he said, potentially smashing through plexiglass windshields or taking out a plane’s wing.

Buehler dismissed concern about the FAA abusing new authorities.

"I didn’t see anything in the statute that said, 'FAA, go out and surveil everyday citizens who happen to want to fly a drone,'" he said. “I think it’s a charge from Congress saying we need to do something about this before one takes out an airliner."

He added: “The FAA doesn’t have the personnel, the wherewithal or the means to spy on these aircraft, for them to assign personnel to do nothing to go out and look for drones. I think this is a situation where they might react to a public complaint or a situation where there’s a regular pattern of interference near an airport or a flight path."

A spokesperson for the FAA said the agency “will need to study the bill carefully and then start the work on its implementation.”

Lisa Ellman, co-executive director of the Commercial Drone Alliance trade group, said the legislation will do more to facilitate rather than hinder legitimate drone use.

“Opportunities for the commercial drone industry had been halted due to these security concerns, and so the legislation opens the door to broader authorities for good actors,” she said.

McKinney, the EFF analyst, said the group remains concerned, and will challenge the law in court if the opportunity arises.

“If you don’t know you’re being surveilled, it’s hard to find standing, and it’s hard to find good cases. But we’re open to being wrong about that,” she said.