From NPR:

Americans are suspicious of drones. Reports of the unmanned aerial vehicles’ use in war zones have raised concerns about what they might do here at home. For instance, in Seattle earlier this year, a public outcry forced the police department to abandon plans for eye-in-the-sky UAV helicopters. The backlash worries Paul Applewhite, an aerospace engineer with 10 years experience at companies like McDonnell Douglas and Sikorski.