[RL] Biometrics and surgery, Fingerprints! Options

[PBTHHHHT]

http://news.bbc.co.uk/2/hi/asia-pacific/8400222.stm

So someone used surgery to alter her fingerprints to bypass the security procedures.

[Karoline]

Wouldn't the fingerprints just grow back like normal once enough layers of skin died?

[Draco18s]

Wouldn't the fingerprints just grow back like normal once enough layers of skin died?

Actually, no. They've transplanted the living cells, not just the surface.

[Karoline]

Actually, no. They've transplanted the living cells, not just the surface.

Yeah, kinda figured that might be why they wouldn't grow back, but I wonder just how much they have to cut off for it to not grow back the original print.

[Jack Kain]

Actually I don't think finger prints grow back, if you disfigure your finger tips yur prints are permanently altered. Of course with disfigurement that just make your prints even more identifiable. They just couldn't be linked back to your old prints. Your prints are formed during fetal development not by genetics this is why even identical twins have different finger prints.

[Karoline]

Actually I don't think finger prints grow back, if you disfigure your finger tips yur prints are permanently altered. Of course with disfigurement that just make your prints even more identifiable. They just couldn't be linked back to your old prints. Your prints are formed during fetal development this is why even identical twins have different finger prints.

Only if you disfigure them enough to leave scars, otherwise if you just burn your fingertips with fire or acid or whatever, it'll grow back after a while.

[Method]

If you read the article carefully they didn't remove her fingerprints altogether they swapped the prints from her left and right hands, effectively altering her fingerprints. This is actually superior to just removing them because having no finger prints would raise more suspicion.

And whether or not your prints grow back is dependent on how many layers of skin are destroyed. People who handle a lot of paper like bank tellers and typists, for example often wear off the superficial layers of their skin and so have no prints, but these grow back. If you damage the deeper layers of the skin, you can get scaring that alters the prints. In this woman's case, I'm sure they did a full-thickness graft, which means the prints would continue to grow unaffected, but being asymmetrical from one hand to the other, they would in effect be changed.

When you think about it, this is actually kind of an elegant solution to the problem of bypassing finger print scans. Of course, all the authorities have to do is reprogram the scanner to also run the print's mirror image against records for the opposite hand, but it would effectively quadruple the amount of timed needed to find a match (at least until the pattern recognition technology improves). What's more interesting is the fact that you could do this with a set of donor prints...

[PBTHHHHT]

When you think about it, this is actually kind of an elegant solution to the problem of bypassing finger print scans. Of course, all the authorities have to do is reprogram the scanner to also run the print's mirror image against records for the opposite hand, but it would effectively quadruple the amount of timed needed to find a match (at least until the pattern recognition technology improves). What's more interesting is the fact that you could do this with a set of donor prints...

My thoughts exactly. Only a matter of time.

[Draco18s]

all the authorities have to do is reprogram the scanner to also run the print's mirror image

Not the mirror image actually. Just scan and run against the opposite hand.

And it would only double the time, as you check the one hand's prints against both hands in the database. No need to make sure that both hands match up, unless you get more than one result, in which case you run the second hand against only that subset.

[Mongoose]

I seriously doubt checking against twice as large a database takes twice as long; that's a piss poor DB design if so.

However, that assumes they HAVE both hands in the DB. Chances are that, if they base the scan off the right index finger, that's the only finger that was scanned into in the DB. So if somebody swaps skin from the left index to the right, well...
And then they can swap from the left ring finger, right ring finger, left middle finger...

And its not like they can call up every person in the system and go "oh, hey, we have a security flaw, can you come in and let us scann all 10 fingers to improve our DB?" They might start doing that with NEW records (especially ones connected to criminals, etc) but for now, they seem screwed.

[Tsuul]

Never realized fingers were near mirror images to those on the other hand.

[Tsuul]

Never realized fingers were near mirror images to those on the other hand.

[Draco18s]

Never realized fingers were near mirror images to those on the other hand.

You obviously never took the "how can I not fail" Fingerprinting merit badge at Boy Scout summer camp.

Of course, I didn't either.

[Mongoose]

Mine aren't; I've got a whorl on the left idexthat isn't on the right (which is just a loop), and my left ring is a near-whorl. I've also got a LOT of print-altering scars- between cooking, welding, and biking... yeah. Left hand is kinda numb, in fact. Wouldn't mind a cyber version.

[Method]

Not the mirror image actually. Just scan and run against the opposite hand.
And it would only double the time, as you check the one hand's prints against both hands in the database. No need to make sure that both hands match up, unless you get more than one result, in which case you run the second hand against only that subset.

Yeah I realized the flaw in my logic after the fact, but I was too busy/lazy to edit. Regardless, as Mongoose has pointed out, switching them from right to left across the board is one thing, but if you start mixing and matching or even rotating distal to proximal, well, good luck with your DB.

Oh, and at least in the US finger prints taken for criminal background checks include all ten digits individually and the four fingers as a group (for reference). (IMAGE)