Re: @fruitoftheloon
That's correct. US law says that census records are sealed for 75 years (length of time might have been different back then), and only summary information is available before that, not individual records, but the Army used them anyway to find the names and addresses of Japanese-sounding people in the US and put them in the relocation camps.
Even for non-illegal uses of census records, there's also the problem of 75-year-old records revealing your mother's maiden name, and for supposedly summary-only data revealing that the number of people in your census tract with a husband of Mexican origin, wife Guatemalan, and three kids is exactly 1, and the US census forms obsess about detail for anybody Hispanic, unlike those of us with Anglo or Celtic origin.
