This topic was raised in another thread: 'Time to Disenfranchise the Old Gits'

Not entirely clear in my head yet whether the concept applies to nations without a written constitution.

Notwithstanding this, should the principle be mandatory for legitimate national government, and should there be any exceptions at all?

Well you've already heard my thin end of wedge argument. And as I said over in the Gits thread, "so many ethical matters fall back upon the dignity and worth of the individual and not the statistical aggregate of social behavior." If a national government is to so assert this worth and dignity, then must not its charter or constitution or whatever document then state that no individual can be excluded on the basis of a social classification? (I mean, sure, maybe criminals forfeit the right because they overtly attack their society - but I don't see any other exceptions which wouldn't have thin wedge problems)

For example, imagine a law based on the statistic that most murders are done by men. So every man is required to submit to thorough psychiatric evaluation before marriage, or purchasing any tools or cookware which could be used to lethal effect, or co-signing a lease or (etc). Other laws might involve forms of surveillance targeting just men. And so on. This would seem to deny a citizen liberty, not through any personal fault or transgression, but because of a social classification, in this case gender.