And then how do you tell Jean Dupont of Paris from Jean DuPont of Dijon?

"Jamie Collins" wrote in message
oups.com...

Amy Blankenship wrote:
That's the point I was trying to make when I said, "Another approach
could be to record their passport number, with perhaps a different
identiifer for locals."

That's one way to do it. What if someone changes his/her citizenship
:-)?

As well as geography, nationality can be complicated by issues of
ethnic origin, culture and politics. That's why I suggested the OP
could use country of permanent residence.

The same person can hold more than one passport, of course.

It's all about the level of trust e.g. sometimes the police are content
to take your name and address, other times they want to see your
driving licence and in more extreme cases they want fingerprints and
DNA samples.

Jamie.

--