Kuro5hin.org: technology and culture, from the trenches
create account | help/FAQ | contact | links | search | IRC | site news
[ Everything | Diaries | Technology | Science | Culture | Politics | Media | News | Internet | Op-Ed | Fiction | Meta | MLP ]
We need your support: buy an ad | premium membership

The Myth of Fingerprints

By Dacta in MLP
Thu Nov 16, 2000 at 07:45:11 AM EST
Tags: Science (all tags)

LingaFranca is carrying a story of a court case challenging the assumption that fingerprints are unique.

While it is true that all fingerprints are unique if you look at enough detail (the molecular level, for instance), it seems that for the purposes of identifying a person they may not be unique enough.

Not only that, but this story argues that identifying fingerprints is a subjective process which depends on the skills of those involved.

(Sorry for the gratuitous Paul Simon reference, BTW. I couldn't resist.)


Voxel dot net
o Managed Hosting
o VoxCAST Content Delivery
o Raw Infrastructure


What's your favorite finger?
o 1st finger 8%
o 2nd finger 8%
o 3rd finger 8%
o 4th finger 3%
o Thumb 2%
o a Scotch finger 7%
o /usr/bin/finger 31%
o This is a really stupid poll 27%

Votes: 104
Results | Other Polls

Related Links
o carrying a story
o Also by Dacta

Display: Sort:
The Myth of Fingerprints | 5 comments (4 topical, 1 editorial, 0 hidden)
I expected better... (4.00 / 4) (#2)
by pb on Thu Nov 16, 2000 at 05:17:59 AM EST

Ok, now I feel like the mass-media just let me down. Can those secret government organizations use a computer to match prints? If so, could they feed these prints in, and search the whole database? If there are no false positives, we don't have a problem. Otherwise, let's see what kind of numbers we're dealing with.

But if matching fingerprints really *is* a Black Art, shouldn't they at least give people a couple partials and say "find the person responsible"? If they can't do that, then they can't match the prints, period, and this shouldn't be considered evidence.

And yes, I took a course in Philosophy of Science; this sort of thing isn't a difficult question; it's an impossible one. The conclusion we came to, basically, is that there's no good way to determine one clear difference between science and religion, or science and pseudo-science. If it's really supposed to be a science, though, you should be able to test it, and see how your hypothesis holds up for now. But there are no guarantees...
"See what the drooling, ravening, flesh-eating hordes^W^W^W^WKuro5hin.org readers have to say."
-- pwhysall
Paul Simon reference? (1.33 / 3) (#3)
by davidduncanscott on Thu Nov 16, 2000 at 10:46:18 AM EST

Birthday paradox (5.00 / 1) (#4)
by Paul Crowley on Thu Nov 16, 2000 at 11:54:45 AM EST

"The first person to fashion a statistical foundation for this assumption was the British gentleman scientist Sir Francis Galton. He calculated the probability that any two fingerprints would resemble each other in all particulars as one in sixty-four billion. "

By my calculations, then, a collection of sqrt(64 * 10^9) ~= 250 thousand fingerprints will probably contain two identical ones. This calculation is based on a whole stack of assumptions, but it's a good rule of thumb(print).
Paul Crowley aka ciphergoth. Crypto and sex politics. Diary.

This shouldn't be TOO surprising ... (none / 0) (#5)
by Bad Mojo on Thu Nov 16, 2000 at 12:57:39 PM EST

As long as the US and other `Free' countries continue to allow freedoms, there will be people comitting crimes and people trying to bring them to justice. It will never be a cut and dry battle. In the US, it all comes down to chance, experience, science, and having a good lawyer. Even when fingerprints are used to place someone at a crime scene, it's rarely an open and shut case on that evidence alone. If anything, truly knowing the odds of people having the same DNA or fingerprints can help a jury or judge make an educated decision about wether someone may or may not be guilty ... or innocent.

Disclaimer: I am from the US and I don't know how other countries operate at this legal level. My mention of Free is in regards to a nation that does not outlaw all things and restrict freedom just to prevent crime. Not that I don't think the US is headed that direction.

-Bad Mojo
"The purpose of writing is to inflate weak ideas, obscure pure reasoning, and inhibit clarity. With a little practice, writing can be an intimidating and impenetrable fog!"
B. Watterson's Calvin - "Calvin & Hobbes"

The Myth of Fingerprints | 5 comments (4 topical, 1 editorial, 0 hidden)
Display: Sort:


All trademarks and copyrights on this page are owned by their respective companies. The Rest 2000 - Present Kuro5hin.org Inc.
See our legalese page for copyright policies. Please also read our Privacy Policy.
Kuro5hin.org is powered by Free Software, including Apache, Perl, and Linux, The Scoop Engine that runs this site is freely available, under the terms of the GPL.
Need some help? Email help@kuro5hin.org.
My heart's the long stairs.

Powered by Scoop create account | help/FAQ | mission | links | search | IRC | YOU choose the stories!