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Category Archives: Fingerprints/Patterned Evidence

Crime and Science Radio: Inside the Los Angeles Regional Crime Lab: An Interview with Dean Gialamas

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This Saturday, February 1, 2014 at 10 a.m. PST join Jan Burke and DP Lyle as they welcome Dean Gialamas, Director of the Los Angles County Sheriff’s Department’s Crime Lab, to the show to discuss this unique lab, what it’s like be be a crime lab director, the new federal forensic science commission, and more!

Dean Gialamas is the former director of the Orange County Crime Lab, the current director of the LASD crime lab, and was recently appointed to the first-ever National Commission on Forensic Science.  He is a past president of the American Society of Crime Lab Directors, and the president-elect of the California Association of Crime Lab Directors.

The Los Angeles County Sheriff’s Department of Scientific Services is an ASCLD/LAB-International/ISO 17025 accredited laboratory that operates from 10 facilities and employs over 300 personnel.  It serves a population of six million residents and over 100 local, state, and federal agencies.

LISTEN

LINKS:

LASD’s Scientific Services

FBI Laboratory Services

The Crime Lab Project

How Stuff Works: How Forensic Lab Techniques Work

Forensic Science Timeline

Experts Named to National Commission on Forensic Science

Announcement of Formation of the National Commission on Forensic Science

LASD Scientific Services Bureau

LAPD Scientific Investigation Division

American Academy of Forensic Sciences

American Society of Crime Lab Directors

American Society of Crime Lab Directors – Laboratory Accreditation Board

International Association for Identification

California Association of Crime Lab Directors

Hertzberg-Davis Forensic Science Center

California Association of Criminalists

Dean Gialamas at NIJ 2010 on Backlogs as a False Metric

Forensic Science Education Programs Accreditation Commission

 

The Writers Forensics Blog: 100 Top Websites to Bookmark

The crew over at FornesicScienceDegrees.org have listed The Writers Forensics Blog as one of their Top 100 Websites to Bookmark, which they describe as a “list of great sites to present practical, real-world information on the subject.” Many great sources here.

Thanks. I’m flattered.

 

 

Breathprints? As Good as Fingerprints?

When we breathe, we take in air which is rich in oxygen (02) and expel air which is richer in carbon dioxide (CO2). The oxygen in the inhaled air is removed by the bloodstream and carried to the body so that the cells will have the oxygen they need to perform all their functions and indeed stay alive. A byproduct of cellular metabolism is CO2, which is picked up by the bloodstream and carried back to the lungs for exhalation. Good air in, bad air out. Simple and clean.

But the exhaled air contains more than just CO2. Hundreds of other molecules and compounds, also byproducts of our metabolic processes, are excreted by the lungs. These can be sampled and analyzed.

It seems that researchers at ETH Zürich and the University Hospital Zürich have begun analyzing exhaled air in the hopes of finding a “fingerprint” that could serve to individualize people. Much as true fingerprints and DNA do.

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So far they have discovered that the chemicals exhaled by a given individual is highly specific and does not change dramatically over time. There are minor variations on a day-to-day basis but in general it seems that a person’s “breath print” is indeed unique. If so this could prove to be another useful method of identification.

Not to mention its medical possibilities. For many years doctors have used the odor of a patient’s breath to help make diagnoses. The odor associated with diabetic ketoacidosis, renal failure, and liver failure are each quite distinct. Though further testing is necessary to prove the diagnosis, it is often suspected from the odor surrounding the patient.

 

Mummies: A New Method For Analysis

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After death, some corpses mummify rather than decay. This more likely will happen in very dry environments but can happen in almost any circumstance. If the corpse dessicates (dries out) more quickly than it decays, mummified remains are produced. These corpses are leathery, dark brown, and appear as if the skin has been “shrink wrapped” over the bones. They also can be very difficult to analyze.

For years, rehydrating finger pads with water, glycerin, and some other liquids, has allowed investigators to obtain fingerprints from mummified corpses. Now it seems that Alejandro Hernandez has found a way to do this with an entire mummified corpse. Very interesting.

 

 

Shoeprints on Clothing: A New Forensic Science Technique

Dr. Kevin Farrugia and his fellow scientists at the University of Abertay have developed a new technique for imaging latent (invisible) shoeprints left on clothing. The finding of any shoeprint is dependent on many factors, not the least of which is the substrate on which the print is laid down. Glass and other smooth, firm surfaces are best, and coarse surfaces such as carpets are often an insurmountable problem for crime scene investigators. Dr. Farrugia modified existing technology to develop his new technique, which could prove useful in future criminal investigations.

 

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Sasquatch Lives!! Maybe

Sasquatch has been a Pacific Northwest mythical creature for many decades. Sitings and even videos have routinely been knocked down and proven to be hoaxes. Not so fast. Now, anthropologist Jeff Meldrum has analyzed some new tracks and has found evidence that they might indeed be real.

 

His evidence?

The toes, as revealed by analysis of the tracks, seem to grip rocks, curl to grab the soil on inclines, and at times splay out presumably for better balance. Things a rubber or plastic fake foot couldn’t easily do. But more importantly, many of the tracks revealed friction ridge patterns. This is important since only primates have such ridges.

 

Another interesting finding was that there appeared to be scars from old injuries on the soles of the feet. When such injuries heal, the dermal ridges tend to curl inward as part of the healing process. Such healing was found here. Something that would be very difficult to fake.

So does this mean that Sasquatch lives? Maybe, maybe not. Hopefully there is more to come.

 

Footprints as Accurate as Fingerprints?

I don’t mean the friction ridge patterns on the soles of our feet. We know these are as individual as the ridge patterns on our fingertips. But what about the pattern with which our feet strike the ground? Could these also provide individualizing evidence? The answer just might be yes.

 

 

 

Each of us walks with a different gait pattern, meaning that our footsteps are aligned and spaced in a unique pattern. Some people march, others swagger, and still others shuffle along. Also the way our foot strikes the ground is unique. If a method can be devised to analyze heel strike, foot roll, and push-off then perhaps this might be useful evidence. In a recent paper published in the British Journal of the Royal Society Interface a group seems to have developed a process for obtaining three-dimensional images of footprints and their studies have revealed that this analysis is highly individual. They quoted and accuracy of 99.6%. If this turns out to be the case, then the analysis of footprints left in sand, soil, or another soft material might prove to be a useful forensic science technique.

 

Q & A: Can the Bruise Patterns on My Victim Be Matched to the Attacker’s Hands?

Q: In a new book, my heroine is framed for a murder that involves a beating through martial arts techniques followed by a fatal push. Are there wound specifics that help authorities determine whether someone was pushed? Could the bruising left by the attacker’s knuckles, hands, or feet be compared to a suspect’s foot or hand?

J. Pearce, Toronto, ON, Canada

A: Pushing almost never leaves bruises that would help distinguish a push from an accidental fall. If the victim were restrained by hand, then bruises that matched the attacker’s fingers might be found on the victim’s arms or legs. It takes a great deal of pressure to restrain someone and this can cause bruising.

The ME might be able to determine whether the bruises and injuries on the victim resulted from a fall or a series of blows with hands or other objects. Rocks and concrete and other objects that the victim might have fallen on can leave bruises just as hands and bats and other weapons do. Often ME can discern a distinctive pattern that would distinguish exactly what made the bruises. Or not. It can go either way.

For example, a rope or a chain used for strangulation or to restrain the victim can leave behind bruises that reveal the braid or link pattern. A blow from a baseball bat or a flat board would leave different bruising patterns—the bat a narrower bruise with diffuse edges and the board a wider bruise with sharper edges. Bite marks often leave bruises that reflect the teeth pattern of the biter and these can sometimes be used to match to a dental impression made from a suspect.

Knuckles could leave a row of round bruises. The size and spacing could be used to rule out certain hands as having delivered the blow while leaving those of a similar size and spacing on the suspect list. The same could be true for the edge of the hand or foot. Either could leave a linear bruise that reflected the thickness of the side of the hand or foot. This would be less clear than would be the knuckles. Again, this could exclude certain suspects.

If the attacker wore a ring with an initial or other distinctive pattern, this pattern could be reflected in a bruise that could be matched to a suspect’s ring.

In your scenario, if knuckle or hand edge bruises were found that did not match the size of your character’s hands then she might be excluded as having made them. If the bruising pattern matched the size of her hands, this would not be conclusive evidence against her but would not remove her from the suspect list.
For more info on trauma patterns, check out HOWDUNNIT:FORENSICS

 



 
 

Guest Blogger: Lisa Black on Fingerprints

THE STATE OF FINGERPRINTS TODAY

One of the most pervasive and annoying myths of those perpetuated by television shows is that a cop somewhere in Nowheresville, Florida can put an unknown print into his computer and search the fingerprints of anyone who has ever been fingerprinted in the United States, including job applicants and military personnel. This is not true. This has never been true, and is unlikely to become true at any point in the immediate future. Someday, yes, but not in time to make the deadline for your next book.

Here’s how it really works: I am a latent print examiner and CSI for a police department in Florida. I scan in unknown prints (generally called ‘latent prints’) collected at crime scenes or from pieces of evidence. I search those against ‘known’ prints, which are the ten fingerprints and two palm prints collected from each person arrested in my town. I can also do a remote search of the database in the next town, because they are on the same software system. I cannot remotely search the county or state database, because they use different software and though the company has been working on a conversion patch for years, it has not yet been accomplished. However, as of about a year ago we are receiving the known prints for their arrestees—apparently that conversion patch has been accomplished—so I am in essence searching their database, but only the past year’s portion of it. With me so far? I have no access to the state database; when a latent goes unidentified, we make a copy for ourselves and then send the original print off to the state, where some counterpart of mine has to scan it and mark its information and redo all the work that I have already done. All of the county goes to the state, so when the state database is searched we’re also searching the county portion that I have not had access to. We have made hits this way (good!) but it takes four to five months (not so good!).

If all of this sounds like a haphazard patchwork of practices, it is. But Rome wasn’t built in a day, and constantly-improving technology is constantly extending my reach (just as we’ve gone from rotary dials to being able to watch videos of your grandchildren on a phone the size of a slice of cheese).

So who does have that all-seeing national database of fingerprints? The FBI…so to speak. Not because they have a supercomputer with tentacles snaking throughout the computers of every police department in the US, but because every police department sends a copy of the known prints they collect to the feds to enter in their database. They receive all job applicants, too, but it used to be these were only checked via classification system to see if the applicant had a criminal history. Now, reportedly, thanks to the ease of modern technology these prints are also being scanned into a searchable database. It does now have military records, but only since 1990.

And these are only known prints. The FBI cannot search every print from every burglary in the US—no computer is that huge. If I had an entire family slaughtered, or some serial killer at work, then we would pack up the latent prints and contact the FBI with our pleading tale and send the prints off to wait in a queue with the other slaughters from across the country. It would take months, not less time than a commercial break while I sit in front of my monitor (which would be quite unhelpfully flashing the picture of every single print it searches…why exactly it would be wasting bytes on such pointless graphics has always been a mystery to me) sipping coffee and looking sexy in my lab coat. This would not be possible, and not only because lab coats are stiff and bulky and quite untailored. I cannot put in an unidentified latent from Nowheresville, Florida and hit on, say, an unidentified latent from Bupkiss, Iowa, thereby connecting our two crimes…maybe the same killer is at work? I’d better get together with the handsome detective in Bupkiss and do a crossover show…alas, no. Things don’t work that way.

Again, if this all sounds haphazard, it is. You can only work with what you got. Here in my little burg we identify a latent print in 11% of our cases in which usable latent prints are submitted. Considering the vast and sundry circumstances at play, this is an excellent record

So go find your local latent print examiner and give her a hug. I can assure you her job looks so much more glamorous on TV.

Lisa Black spent the five happiest years of her life in a morgue, working as a forensic scientist in the trace evidence lab until her husband dragged her to southwest Florida. Now she toils as a certified latent print analyst and CSI at the local police department by day and writes forensic suspense by night. Her fifth book, Trail of Blood, involves the real-life Torso Killer, who terrorized Cleveland during the dark days of the Great Depression.

 

Twins, DNA, and Fingerprints

In 2008 police in Gwinnett, Georgia arrested Donald Smith for carjacking and murder. There was no doubt that they had their man. Witnesses identified him, a nearby security camera backed them up, and DNA evidence found at the scene matched Donald. Donald insisted they had the wrong guy and that the crime must’ve been committed by his twin brother. Yeah, right. We’ve heard this one before.

But fingerprints found at the scene did not match Donald but rather his brother Ronald. It turns out that they were identical twins and therefore shared DNA but not fingerprints. Donald was telling the truth and brother Ronald found himself in custody.

It was a similar case that brought down Bertillonage, the anthropometric identification system devised by Alphonse Bertillon in 1882. The need for a foolproof method of identification had dogged criminal investigations for many years. Eyewitness accounts were all that was really available. But Alphonse devised his system to correct this deficiency. Fortunately around the same time Sir Francis Galton, William Herschel, and Sir Edward Henry were doing their landmark research into fingerprints. The result was a clash of these two systems in the famous Will West case.

First a little background:

Anthropometry (anthrop means human; metry means to measure) is defined as the study of human body measurements for use in anthropological classification and comparison. Simply put, it is the making of body measurements in order to compare individuals with each other.
Using anthropometry, French police officer Alphonse Bertillon developed the first truly organized system for identifying individuals in 1882. Believing that the human skeleton did not change in size from about age 20 until death and that each person’s measurements were unique, he created a system of body measurements that became known as bertillonage. According to Bertillon, the odds of two people having the same bertillonage measurements were 286 million to one.

This belief led Bertillon to state that all people could be distinguished from one another by key measurements, such as height, seated height from head to seat, length and width of the head, right ear length, left little finger length, and width of the cheeks, among others. His greatest triumph came in February 1883, when he measured a thief named Dupont and compared his profile against his files of known criminals. He found that Dupont’s measurements matched a man named Martin. Dupont ultimately confessed that he was indeed Martin.

For many years, this system was accepted by many, but by the dawn of the 20th century cracks began to appear. The measurements were inexact and subject to variation, depending upon who made them. And because the measurements in two people who were of the same size, weight, and body type varied by fractions of a centimeter, flaws quickly appeared and the system was soon discontinued. Its death knell tolled with the famous Will West case.

Though landmark in its importance, this case was an odd comical coincidence. On May 1, 1903, Will West came to Leavenworth Penitentiary in Kansas. The records clerk apparently thought that the man looked familiar, but the new inmate denied ever having been in the prison before. As part of his intake examination, anthropometry was performed and officials were surprised to find that Will’s measurements exactly matched those of William West, another inmate at Leavenworth. The two men even looked eerily similar as if they were twins.

They were brought together into the same room, but each stated that they were not brothers. Fingerprints were then used to distinguish between the two Wills. Leavenworth immediately dumped anthropometry and switched to a fingerprint-based system for identifying prisoners. New York’s Sing Sing Prison followed a month later.

But was the similarity between Will and William West just a bizarre coincidence? Not really. A report in The Journal of Police Science and Administration in 1980 revealed that the two actually were identical twins. They possessed many fingerprint similarities, nearly identical ear configurations (unusual in any circumstance except with identical twins), and each of the men wrote letters to the same brother, same five sisters, and same Uncle George. So, even though the brothers denied it, it seemed that they were related after all.

 
 
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