Invasion of the drones.

• Author: Smith, Patricia
• Position: TECHNOLOGY

You've probably heard about Domino's testing drones as a last way to get pizza to your door. And drones are already being used by everyone from farmers and scientists to Hollywood directors. But the presence of thousands of these unmanned aerial vehicles in the sky also raises questions. Here's a look at three major areas of concern.

1. PRIVACY

   Sunbathing topless in the privacy of her secluded backyard near Melbourne, Australia, Mandy Lingard dismissed the buzzing she heard overhead as coming from some kind of toy. In fact, it was a drone, hired by a real estate agent to take aerial photos of the property next door to her house. Lingard was later horrified to discover a picture the drone had taken showing her mostly naked body in billboard real estate ads.

   It's not just Australia where your privacy could be threatened by a small battery-powered device with a camera. In the U.S., non-military drones are a $450 million industry, used by everyone from hobbyists and farmers to scientists and Hollywood directors.

   Drones also have uses in law enforcement. Police departments use them for search-and-rescue operations or to monitor dangerous situations. But some privacy experts are worried about other possibilities.

   "Our biggest concern is that they not be used for mass surveillance," says Jay Stanley of the American Civil Liberties Union (A.C.L.U.). "We don't want the government hovering over our cities and towns 24/7 and tracking everywhere that everyone goes."

   The Fourth Amendment protects Americans from "unreasonable searches and seizures." That's traditionally meant that police must either get a court-issued warrant or have "probable cause" to search a person or their property. But the Framers couldn't have imagined a police drone hovering overhead with a video camera: Does that constitute an "unreasonable search"?

   Lawmakers are trying to address these concerns. Twenty states have passed laws regulating the use of drones. Most address privacy concerns by requiring warrants for surveillance or specifying how police can use them. In the meantime, keep an eye on the sky if you're sunbathing.

2. SAFETY

   Last spring, a 375-pound drone operated by the Pennsylvania Army National Guard crashed outside an elementary school near Harrisburg, Pennsylvania. (School was out and no one was hurt.)

   In the past few months, there have been dozens of near-misses between drones and planes, including several at airports in New York, Los Angeles, and Washington, D.C...