From: Black Unicorn <unicorn@schloss.li>
Date: Sat, 18 May 1996 18:29:48 +0800
To: "Paul S. Penrod" <furballs@netcom.com>
Subject: Re: Fingerprinting annoyance
In-Reply-To: <Pine.3.89.9605151204.A27377-0100000@netcom6>
Message-ID: <Pine.SUN.3.93.960515194016.10635M-100000@polaris.mindport.net>
MIME-Version: 1.0
Content-Type: text/plain


On Wed, 15 May 1996, Paul S. Penrod wrote:
> On Tue, 14 May 1996, Black Unicorn wrote:
> > Paul S. Penrod wrote:

> > > I know of no such instance (other than some informal "fingerprint the 
> > > kiddies for safety" schtick) where it's a do-it--yourself operation. 
> > 
> > Not _technically_ perhaps.  But in most cases it's a
> > go-down-to-the-police-station-and-have-them-sign-the-card operation.  Who
> > is it that can tell a random signature from a police signature exactly?
> > Like I said, standard print cards are available at the GPO.
> 
> Thats fine, but tell me it's going to play at the clearance level...It 
> won't.

Agreed.  I never claimed this.

> > > Doesn't always work. Partials can be extrapolated to yield a
> > > relative match.
> > 
> > Depends on what you are looking to do.  If your goal is to deter random
> > searching through a national database, mutilation will probably be very
> > effective.  If they have the prints of the murderer (you) and you're a
> > suspect, mutilation aside from actually removing the fingers isn't going
> > to do anything.
> 
> If there is a serious crime involved, partials are sufficient to make the 
> "guest list" if there are other mitigating factors to even suspect you 
> might be involved. That's doesn't mean you'll make it to the top, but it 
> can certainly cause some painful scrutiny.

Again, it depends on the degree of "mutilation."  Distortion of major
features is fairly effective even against partial attempts which are
matched by computer.

[Laytex]

> > > Wont work. The hands are checked first for signs of tampering.
> > 
> > See above about tech end around.
> 
> Again, process will work, but not allowed in context of clearance.

Concur.

> Scraping the fingertips runs the risk of leaving trace marks that are 
> just as good as the ridges you tried to remove - even better if you've 
> left finger prints as a result. The point to the game is not to search 
> any database, but to produce a verifiable match with evidence at the 
> scene of any crime. In the case of a clearance, it is to start or 
> validate an identification process. IF validation is unobtainable via 
> fingerprints, then the issuing body can employ other means (such as 
> retinal scans) or deny clearance all together.

Careful.  Even Central Intelligence Agency print requirements are for
criminal background check only.  They will run through FBI files and so
forth and keep the prints for their records, but they are rarely if ever
used as identification verification per se.

This is because not everyone in the world has fingerprint files floating
around.  If you are getting printed for the first time ever and you
distory or mutilate, there's nothing to compare to.  Further, if you just
distort, you're prints later might not match well when computer searches a
nationwide database (which excludes CIA employees in any event).

It's all about application.

To repeat, if you're looking to "estlablish" a false print index,
distortion is a good way to do it.

If you're looking to evade a search which has already narrowed you down
well, hack off some fingers.

> ...Paul

---
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