Well this is probably not legit because regardless of circumstance or intent it's perfectly legal to record anything in a public place. If the guy was recording on private land however it is illegal it's just hard to tell if that's the case since it doesn't say it was on private land only that it was recording. It's also a good idea for people to remember that if your window is open to the public and you might be naked or doing sexy stuff or w/e, that someone might be able to see into it and so curtains were invented to prevent this issue/problem.

edit: it is actually legit however it doesn't say if the person was recording on public land or not which if it was public land then it's not illegal and this does include being in the air. http://www.upi.com/Odd_News/2016/12/05/Utah-police-seek-owner-of-window-peeping-drone-loaded-with-voyeur-videos/9191480963549/

also according to this report http://fox13now.com/2016/12/05/orem-police-say-theyve-identified-peeping-drone-operator/ the person in question had a previous charge of voyeurism however it was from him looking over the changing stalls at tanning salons.