government cracking down on certain types of speech by members of the military branches attorney as john whitehead he joins me now from charlottesville virginia to break down what this could mean on a larger scale and john what do you make of the results of this report. well again if you're on a social network such as facebook and you say something the government doesn't like and gets in a lot of trouble with brandon rodd i mean you have the article the security the f.b.i. the local police arrive and arrest him and he asked what he did they said controversial postal facebook he was with them illustration luckily we found a judge that let him out within a week but a lot of people disappear so it seems here that if you're socially withdrawn you don't have a life close family members that's one of the so-called risk factors or you're participating in chassell facebook and you appear to be anti american and year low these are all interpretations so it has to come up with the what is anti american you don't like the way you don't you're against the war in afghanistan well i know a lot of people say les

great reading room in the public library and there's a line from whitehead that says we went on this tremendous adventure together, johnfter a portrait of snow has hung in my library to remind me of that momentous week we spent together and how it changed all of our lives and all i look up to him. i started cheering up in the library. they were friends after all. people were looking at me like what is he doing? so captivating. that is one of my great research >> host: in story of london's most terrifying epidemic--and how it changed science, cities, and the modern world" you write the construction of the new sewers was as epic and undoing as the building of the eiffel tower. if snow and whitehead's investigation showed her intelligence that come to understand a massive health crisis, sewers proved you could actually do something about it. >> guest: there is a whole urban infrastructure appreciation that i think we need to have more of and one of the best thing for me as an author with the "the ghost map: the story of london's most terrifying epidemic--and how it changed science, cities, and the modern world" is after t