I think it's very hard to anticipate how every given person in a large population uses communication tools. When former Florida governor Jeb Bush began his campaign for presidency, he released all the emails he sent/received as governor. This is something mandated by Florida's very open public records laws:
As it turned out, the cache of thousands of emails contained things that are hard to anticipate. Including people emailing their SSN, or talking about their employment/medical issues; the former is possible to filter out computationally, the latter would require manual review and judgment. Bush was criticized, and in response, he took down the emails temporarily until employees could clean them up. But AFAIK, he didn't do anything illegal, because he mirrored exactly what was available from the state official archive which, again AFAIK, did not alter its copy.
This is similar to AOL's release of its search logs. It thought anonymizing user identities would provide anonymity, but they did not realize that some users write very personal things into the search box: https://en.wikipedia.org/wiki/AOL_search_data_leak
https://www.theverge.com/2015/2/10/8013531/jeb-bush-florida-...
As it turned out, the cache of thousands of emails contained things that are hard to anticipate. Including people emailing their SSN, or talking about their employment/medical issues; the former is possible to filter out computationally, the latter would require manual review and judgment. Bush was criticized, and in response, he took down the emails temporarily until employees could clean them up. But AFAIK, he didn't do anything illegal, because he mirrored exactly what was available from the state official archive which, again AFAIK, did not alter its copy.
This is similar to AOL's release of its search logs. It thought anonymizing user identities would provide anonymity, but they did not realize that some users write very personal things into the search box: https://en.wikipedia.org/wiki/AOL_search_data_leak