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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.

 
 
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