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Monday, June 3, 2002

BREAKING NEWz you can UzE...

Fingerprint IDs raise privacy issues - CNN MSNBC - 6-2-02  ... program run by Oakland, California-based Indivos Corp. that links customers' fingerprints with their credit or debit cards, allowing them to buy groceries by...

Exact copy (cloning) impossible, says physicists (*sarcastically* Wow!! Really???)

It's BidNow week!  Up for sale this week are two individual auctions containing one CLPEX.com t-shirt of your size!  As usual, they start at one penny so everyone can get in on the fun.  If you want to donate more than $20 for maintenance and upkeep at CLPEX.com, then perhaps this is the place!  If nobody bids high, here is a chance to get a great deal! 

Good morning via the "Detail," a weekly e-mail newsletter that greets latent print examiners around the globe every Monday morning. The purpose of the Detail is to help keep you informed of the current state of affairs in the latent print community, to provide an avenue to circulate original fingerprint-related articles, and to announce important events as they happen in our field.

Last week, we looked at several SWGFAST drafts for comment and two more anti-fingerprinting articles.  If you didn't get a chance to review these, visit the Detail Archives.  Last week we also finalized plans four our CLPEX.com t-shirts which are now ready to order!!  Just visit the "CLPEX.com 2002 t-shirt" order page of the website (on the left side of the home page under Website Features), or reply to this e-mail with your size and shipping information.  A confirmation e-mail gives payment info (where to send your $20)  I would suggest at LEAST check out the pictures of the shirts on the site!!  They turned out GREAT!!

This week we turn to a recent Florida Supreme Court ruling that serves as a warning to every area of forensic science.  You better have your science down and be able to articulate it!


Supreme Court of Florida

Appeal: judgment and sentence of the trial court imposing the death penalty on Joseph J. Ramirez following his third trial for the first-degree murder of a night courier.  (prior reversals were based on trial court admission of testimony regarding the knife-mark identification procedure detailed below)


Relevant facts:

The body of a Federal Express worker was discovered in the Miami building where she worked.

She had died of multiple stab wounds to her body and blunt trauma to her head.

Additional injuries included cuts on her hands and back and one stab wound into her chest cartilage.

A mail bag containing approximately $430 was missing.

A bloody fingerprint identified to Ramirez was found on a doorjamb near the victim's body

Investigation revealed Ramirez had cleaned the building that afternoon, inquiring about revenue coming in.

In the search of the car of the girlfriend of Ramirez a knife was found.

The girlfriend testified that the knife was kept in her car for protection, that she had found in her kitchen sink after the dates of the incident, that she had washed it and returned it to the car.  Traces of blood were detected on the knife, but were insufficient for further testing.

The knife and wound were examined in the below manner, and was identified as being the specific knife which produced the victim's chest wound.


Robert Hart: Criminalist specializing in firearm and tool mark identification with the Miami-Dade Police Department, been in the field since 1971.


p. 18+  "Hart's testing procedure is based on the premise that every knife blade is unique due to microscopic imperfections in the steel caused by the manufacturing process.  These imperfections, he contends, leave lines - i.e., striations - when a knife is plunged into human cartilage, and because cartilage is a relatively firm material, as compared to human flesh, it retains the marks.  The striations in the cartilage, i.e., the striation 'signature,' may be matched by a skilled technician to the imperfections in the blade of the knife that made the wound.

Hart employs the following technique:  (1) he conducts a mock stabbing with the suspected knife in a test medium; (2) he separates the cut faces of both the incision in the exemplar and the incision in the victim's cartilage; (3) he makes a hard cast of the cut faces of both incisions; (4) he compares the casts under a firearms comparison microscope to match up the striations; (5) he makes a subjective determination concerning the degree of the match; and (6) if the marks are sufficiently similar - ie., if the striation 'signatures' are sufficiently similar - he concludes to a degree of scientific certainty that both incisions were made by the suspected knife to the exclusion of every other knife in the world.

According to Hart, a technician's ability to identify microscopic similarities in casts is developed by training and is passed on from one technician to another in the workplace.  A 'match' under this method is declared if there is 'sufficient similarity' in the striated marks on the cast to eliminate the possibility of coincidence. 

After Hart explained the principle underlying his testing procedure for the knife mark identification, he testified that "The result of my examination made from the microscopic similarity, which I observed from both the cut cartilage and the standard mark, was the stab wound in the victim was caused by this particular knife to the exclusion of all others."

p.22  Verification:  "One of the State's experts, Lonny Harden ('a forensic scientist in firearm and tool mark identification'), testified that he too examined the evidence prepared by Hart in the present case and agreed with Hart that Ramirez's knife was the murder weapon to the exclusion of all other knives."

p.20-21  Other methodology verifications: 

Monty Lutz, forensic scientist in firearm and tool mark identification in Milwaukee, Wisconsin: "has never made a knife mark identification in cartilage, but that the principle underlying such a practice is generally accepted in the field"

William Conrad, formerly a forensic scientist in Virginia, "has tested consecutively manufactured knives and that each left distinct identifying marks and that Hart's theory appears to use procedures accepted in the field"

John Cayton, chief forensic firearm and tool mark examiner with the Kansas City Crime Laboratory, "testified generally concerning tool mark identification procedures"

Richard Souviron, dentist and consultant in forensic odontology in Dade County, "the use of hard casts is generally accepted in the field as a method of analyzing wounds made in human tissue"

Defense witness, Dale Nute, forensic science consultant with a doctorate in criminology from Florida State University, "knife mark identification has not been properly validated..." "...because Hart's procedure applies to an unusual receiving material, i.e., cartilage, and involves a stabbing rather than cutting motion, it cannot be assumed that this method is as reliable as other tool mark comparisons..."  "...it is not scientific to say 'it was a match because I say so,' as Hart does, rather than using objective criteria and articulating the bases for making an identification."

p. 19-20  This determination is entirely subjective and is based on the technician's training and experience; there is no minimum number of matching striations or percentage of agreement or other objective criteria that are used in this method.  No photographs are made of the casts, Hart explained, because lay persons and those not trained in this procedure would be unable to understand the comparison process; similarly, no notes are made describing the basis for identification.  Once a match is declared under his theory, no other knives are examined because an identification under this method purportedly eliminates all other knives in the world as possible sources of the wound.  Under Hart's method of identification, a team of expert technicians trained by him would be virtually impossible to challenge notwithstanding the fact that his procedure is untested and yet to be accepted by the relevant scientific community.  There is no objective criteria that must be met, there are no photographs, no comparisons of methodology to review, and the final deduction is in the eyes of the beholder, i.e., the identification is a match because the witness says it is a match."

At the conclusion of the above testimony, the trial court had ruled that the evidence was admissible.

p.15  "Traditional 'knife mark' evidence is a subgroup of the broad category of evidence commonly referred to as 'tool mark' evidence.  The theory underlying tool mark evidence, which is explained below, is generally accepted in the scientific community and has long been upheld by courts."

Supreme Court Comments:

p.24  "... the State submitted no substantive proof of scientific acceptance of... testing and... reliability"

p. 25 "... the record does not show that Hart's test has ever been subjected to meaningful peer review or publication..."

p. 27  "[Hart] testified that the examining technician generally takes no photomicrographs of the casts because lay persons would be unable to understand the identification process,... [however] ...photos are instrumental in confirming... the validity of the 'match.'"

p.28 "[Hart] ...testified that they do not prepare notes or written reports delineating the basis for identification because to do so would not be helpful... [however] ...descriptions, too, are helpful in confirming the validity of the 'match.'"

p.28 "The record does not show that the error rate for Hart's method has ever been quantified."

p.28-29 "The record does not show that this method is governed by objective scientific standards.  The State's experts repeatedly testified that the method is entirely subjective and that objective standards would be impractical."

p.29  "...the record contains no written authority... that upholds his current methodology."

Supreme Court Conclusions:

p.  23  "...we conclude that this testimony standing alone is insufficient to establish admissibility under Frye in light of the fact that Hart's testing procedure possesses none of the hallmarks of acceptability that apply in the relevant scientific community to this type of evidence.  This is particularly true in light of the extraordinarily precise claims of [certain] identification... in a criminal..., capital..., proceeding."

P.13:  "A bald assertion by the expert that his deduction is premised upon well-recognized scientific principles is inadequate to establish its admissibility if the witness's application of these principles is untested and lacks indicia of acceptability."

P.13:  "The trustworthiness of expert scientific testimony is especially important because oftentimes 'the jury will naturally assume that the scientific principles underlying the expert's conclusion are valid.'

p.29 "We conclude that the State has failed to show by a preponderance of the evidence that Hart's procedure is generally accepted by scientists active in the field to which the evidence belongs.  ...'the burden is on the proponent of the evidence to prove the general acceptance of both the underlying scientific principle and the testing procedures used to apply the principle to the facts of the case at hand."

p.30 "We hold that... testimony based on Hart's knife mark identification procedure, which we find to be new and novel, does not reach the threshold for admissibility under Frye and is therefore unreliable and inadmissible."

p.33 "In sum, Hart's knife mark identification procedure - at this point in time - cannot be said to carry the imprimatur of science.  The procedure is a classic example of the kind of novel 'scientific' evidence that Frye was intended to banish - i.e., a subjective, untested, unverifiable identification procedure that purports to be infallible.  The potential for error or fabrication in this procedure is inestimable.  In order to preserve the integrity of the criminal justice system in Florida, particularly in the face of rising nationwide criticism of forensic evidence in general, our state courts - both trial and appellate - must apply the Frye test in a prudent manner to cull scientific fiction and junk science from fact."

p. 35: Conviction for first-degree murder, armed robbery, and armed burglary with an assault REVERSED; sentences VACATED.


As usual, for informal banter about the weekly Detail, visit
the CLPEX chat board (http://www.clpex.com/phpBB/viewforum.php?f=2)   And the onin.com forum (http://onin.com/fp/wwwbd/) is available for more formal discussion.

In the works:

(hopefully soon) Recommendations from the Forensic Fingerprint Forum held in Chicago several weeks ago, coordinated by Joe Polski. (being held up in review by attendees)

An interesting case worked by Doede Rijpkema.  You would be hard-pressed to top this bizarre AFIS identification!

If you have an interesting case or an article for publication in the Detail, attach to an e-mail to kaseywertheim@aol.com

UPDATES on CLPEX.com this week...

Created the T-shirt page off the main web page for this year's 2002 CLPEX.com t-shirt.

Working on updating the CLPEX.com bookstore... details next week...

Feel free to pass the link to The Detail along to other examiners. This is a free service FOR latent print examiners, BY latent print examiners. There are no copyrights on The Detail, and the website is open for all to visit.

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Until next Monday morning, don't work too hard or too little.

Have a GREAT week!


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