Why stop with users? Every email, web search, Lyft ride, Dropbox file, Facebook post and Grindr encounter could get its own canary: "This message has never been disclosed to law enforcement".
And as @chiph says, the canary doesn't really have to die after a secret warrant is served, it just needs to sing a different song: "Your data has not been disclosed to law enforcement for [ 179 ] days".
And as @chiph says, the canary doesn't really have to die after a secret warrant is served, it just needs to sing a different song: "Your data has not been disclosed to law enforcement for [ 179 ] days".
https://news.ycombinator.com/item?id=8336323