As a former police officer who has taken hundreds of fingerprints I
can say that each finger of the same person has the potential to have
a different pattern. It is entirely coincidence if they seem to have
the same pattern on each of their fingers. But if one looks closely,
each of those basic patterns will be slightly different.
Perhaps they could try this experiment to see the results?
Electronic Privacy Information Center
?Fingerprint patterns are created from the ridges on your fingers. The
patterns, consisting of loops, whorls and arches, have been shown to
be unique between people. Even on a single individual, each of the ten
fingers has a different pattern.?
Authentication Methods Used for Banking
?Even each finger for the same person has a different pattern. This
even holds true for identical twins. (Smith, 2005) Because of this
fact, fingerprint authentication is an excellent way to differentiate
I hope this answers your question. If it does not, or the answer is
unclear, then please ask for clarification of this research before
rating the answer. I shall respond to the clarification request as
soon as I receive it.