In a bid to "cleanse" the database before online renewal begins, 4.5 million passport photos were matched against each other by facial recognition technology - a total of 21 trillion biometric checks.47 might not seem like that many but New Zealand isn't a huge country.
Of those, 210,000 possible matches had to be checked by human eyes and most were discovered to be clerical or imaging errors or identical twins.
But the checks found 47 false passports.
When I looked it up to see how many Kiwis there are I found this government estimate of 4,434,186, which leads me to assume that there was more than one photo per passport holder because there were more photos analysed (4.5 million) than New Zealand has citizens.
