If the angle's right. Not from directly above, it would have to be imaging from a pretty oblique angle...which I don't even know if they can realistically do, as I don't know the pan limitations of their cameras.
Of course there's other possibilities - signals interception (how many people talk on a cordless phone?) for example. But there's a fundamental point of law here that, if you're putting something "in plain view", privacy doesn't apply. There's nothing anywhere that says a government agent right now can't look through an open window, be it with binoculars or a recon drone. As far as I know, people in cordless phone conversations have a "reasonable expectation of privacy"...but given that they broadcast so that any yahoo with a police scanner can listen in, and that law enforcement can already cruise the streets and scan for electronic signals coming from houses without a warrant (for example; looking for the radio emissions from UV lamps used to grow pot, which has been done and upheld in court), I'd expect the cordless phone exception to disappear any day now.
Really, using recon drones for law enforcement isn't going to break any legal protection that hasn't already been shredded in other decisions. There's no fundamentally new surveillence capability a Predator provides that would somehow create new abuses of legal rights.