mr. calo, you talked about supreme court cases regarding the constitutionality of aerial surveillance, which we have read. do you believe that that body, supreme court cases, are adequate for -- to guide the courts and law enforcement in the area of unmanned surveillance? >> i'm not sure that i even think they are adequate to -- for purposes of manned surveillance. but with unmanned surveillance there is an additional danger that as the costs go down you see more of it. and so, no, i'm not sure they are adequate. i think they need to be updated. >> thank you very much. senator grassley. >> professor calo, the supreme court has held observations made while flying a manned aircraft in navigable airspace over a person's property does not violate the fourth amendment. in several cases police were allowed to conduct surveillance over private property at heights ranging from 400 feet to 1,000 feet. question -- how long must a drone fly over private property before it triggers a reasonable expectatio

mr. calo, go ahead. >> thank you commensurately economic member grassy members of the committee for the opportunity to testify today. as he munched on a law professor mostly here to answer your question and so i won't read my testimony you have before you in the record. a couple quick points by way of summary. first his folks are very worried about the privacy implications of drones thus are well-founded. especially because drones drive down the cost of surveillance considerably and turn incidents will go a. american concerns are legitimate for another reason, which is there's very little in american privacy law that would limit for surveillance. just a couple examples of that. there's no privacy in public or from a public vantage. there's no privacy in contraband and said the idea is you could imagine drones flying around, not the one on the table, but the ones that exist today in department of homeland security is akin to that of fly around the censors before trace amounts of drugs and so fo

mr. chairman. >> thank you, senator hirono. >> to all the panelists, ryan calo, your personal mission that the fourth amendment only applies to state actors. so at least there are protections for against unreasonable government intrusion. my concern centers around what happens when 9 state actors can utilize this technology and after 2015 the sky is the limit. do you think congress has the power to prohibit private citizens and corporations from using drones with cameras that are capable of storing images or in fact what is the limit to what congress can do to provide limitations on non state actors and their use of drones? >> i think congress can provide those limits. the first amendment draws a distinction between stopping someone from talking about something and general prohibition. the government may say that you are not allowed to do x, y and z in order to gather information and that can apply across to the press and individuals or whoever else it might be. so as a consequence yes, they probably can. they wouldn't be able to make content based distinctions about who news drones and who can't but