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Category Archives: crime lab

Crime and Science Radio: Crime Scenes, Criminalistics, and the Cutting Edge

Crime and Science Radio: Crime Scenes, Criminalistics, and the Cutting Edge in Los Angeles: An Interview with Former LASD Criminalist Professor Donald Johnson of California State University, Los Angeles

BIO: Professor Donald James Johnson is an expert on criminalistics, with emphasis on crime scene investigation and reconstruction (homicides and sexual assaults), and forensic biology. His research interests include the application of new technologies to the field of criminalistics. He was formerly a senior criminalist at the Los Angeles County Sheriff’s Department, where he was involved in the scientific investigation of violent crimes.

NOTE: This show was recorded live at the MWA-LA Chapter meeting in Los Angels, CA

LISTEN: LISTEN: http://www.blogtalkradio.com/suspensemagazine/2016/09/10/crime-and-science-radio-with-special-guest-dr-donald-james-johnson

Link will go live Saturday 9-10-16 at 10 a.m. Pacific

LINKS:

California Forensic Science Institute: http://www.calstatela.edu/hhs/cfsi

School of Criminal Justice and Criminalistics at CSULA: http://www.calstatela.edu/hhs/crim

CSULA Masters in Criminalistics http://ecatalog.calstatela.edu/preview_program.php?catoid=11&poid=3452

Los Angeles County Sheriff’s Department Scientific Services video: https://www.youtube.com/watch?v=SboLJ7WwnXQ

Los Angeles County Sheriff’s Department: http://sheriff.lacounty.gov

American Academy of Forensic Sciences http://www.aafs.org

 

Q&A: Will a Decaying Corpse Actually Produce Alcohol?

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Q: Is it possible or likely for blood alcohol levels to increase or decrease in a decomposing body, and if so during what stages of decomposition?

A: Alcohol is usually consumed in the decay process but may actually be produced and this might cloud any toxicological examinations on the corpse. Make it look as if the victim consumed more alcohol than he actually did.

I must point out that alcohol is not commonly produced but it does happen in rare cases. The alcohol is a byproduct of the action of some types of bacteria that are involved in the decay process. This means that alcohol can only appear during active decay. What is that time period? A little about putrefaction.

The decomposition of the human body involves two distinct processes: autolysis and putrefaction. Autolysis is basically a process of self-digestion. After death, the enzymes within the body’s cells begin the chemical breakdown of the cells and tissues. As with most chemical reactions the process is hastened by heat and slowed by cold. Putrefaction is the bacterially mediated destruction of the body’s tissues. It is this decay that might cause some alcohol formation. Not always, but sometimes. The responsible bacteria mostly come for the intestinal tract of the deceased, though environmental bacteria and yeasts contribute in many situations. Bacteria thrive in warm, moist environments and become sluggish in colder climes. Freezing will stop their activities completely. A frozen body will not undergo putrefaction until it thaws.

Under normal temperate conditions, putrefaction follows a known sequence. During the first 24 hours, the abdomen takes on a greenish discoloration, which spreads to the neck, shoulders, and head. Bloating follows. This is due to the accumulation of gas, a byproduct of the action of bacteria, within the body’s cavities and skin. This swelling begins in the face where the features swell and the eyes and tongue protrude. The skin will then begin to “marble.” This is a web-like pattern of the blood vessels over the face, chest, abdomen, and extremities. This pattern is green-black in color and is due to the reaction of the blood’s hemoglobin with hydrogen sulfide. As gasses continue to accumulate, the abdomen swells and the skin begins to blister. Soon, skin and hair slippage occur and the fingernails begin to slough off. By this stage, the body has taken on a greenish-black color. The fluids of decomposition (purge fluid) will begin to drain from nose and mouth. This may look like bleeding from trauma, but is due to extensive breakdown of the body’s tissues.

The rate at which this process occurs is almost never “normal” because conditions surrounding the body are almost never “normal.” Both environmental and internal body conditions alter this process greatly. Obesity, excess clothing, a hot and humid environment, and the presence of sepsis may speed this process so that 24 hours appear like 5 or 6 days have passed. Sepsis is particularly destructive to the body. Not only would the body temperature be higher at death, but also the septic process would have spread bacteria throughout the body. In this case, the decay process would begin quickly and in a widespread fashion. A septic body that is dead for only a few hours may appear as if it has been dead for several days.

As opposed to the above situations, a thin, unclothed corpse lying on a cold surface with a cool breeze would follow a much slower decomposition process. Very cold climes may slow the process so much that even after several months, the body appears as if it has been dead only a day or two. Freezing will protect the body from putrefaction if the body is frozen before the process begins. Once putrefaction sets in, even freezing the body may not prevent its eventual decay. If frozen quickly enough, the body may be preserved for years.

So, whether a particular corpse actually produces alcohol or not is totally unpredictable. How long it takes depends upon the conditions the corpse is exposed to. In a corpse in an enclosed garage in Houston in August, this process will be very rapid and the corpse will be severely decayed after 48 hours. If parked in a snow bank in Minnesota in February it might not even begin the decay process until April or May when the spring thaw occurs. And anything in between. The appearance of any alcohol would coincide with the time frame of the bacterial activity.

So how does the ME get around this possibility? How can he determine the actual alcohol level that was present prior to the decay process kicking in? He can’t with any absolute accuracy, but he does have a tool that will help him make a best guess. He can extract the vitreous humor from the victim’s eye—this is the jelly-like fluid that fills the eyeballs. The alcohol level within this fluid matches that of the blood with about a two-hour delay. That is, the level within the vitreous at any given time reflects the blood alcohol level that was present approximately two hours earlier. And the vitreous is slow to decay so it might be intact even though the corpse is severely decayed. By measuring the vitreous level the ME will know the blood alcohol level two hours prior to death and he can then estimate the blood alcohol level at the time of death.

 

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This question originally appeared in MORE FORENSICS AND FICTION

http://www.dplylemd.com/book-details/more-forensics-and-fiction.html

 

Crime and Science Radio Goes Live at MWA-LA

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Mark your calendars for this event. Jan and I are recording an episode of Crime and Science Radio live with our special guest Criminalist and Forensic Science Professor Don Johnson. This will be a fun and informative event. Sign up now.

From MWA-LA

We have a special luncheon planned in August:

D.P. Lyle and Jan Burke Live Radio Podcast with special guest interviewee Criminalist and Forensics Professor Don Johnson

This will be a unique opportunity to experience a live podcast with three outstanding experts

Sunday, August 7, 2016

Tam O’Shanter Restaurant

2980 Los Feliz Blvd.

Los Angeles

Doors open at 11:30

MORE INFO:

http://www.socalmwa.com/2016/05/tam-luncheon-dp-lyle-jan-burke-live-radio-podcast/

 

Crime and Science Radio: Forensic Science Then and Now: an Interview with Forensic Scientist Jay Jarvis

Join Jan Burke and Dr. Doug Lyle for an interview with prominent forensic scientist Jay Jarvis, who has over 35 years of experience in working in the field. He has served on the American Society of Crime Lab Directors/Laboratory Accreditation Board, and has written a history of the establishment of the first crime lab in Georgia. He currently operates a private forensic lab, Arma Forensics, which specializes in firearms evidence, and is active in his church and community. He’ll talk to us about forensic science, past, present and future; lab accreditation; firearms evidence; private labs, and more.

 

Jarvis headshot

 

BIO: Jay Jarvis is a native of Long Island, New York. While a student in high school, his chemistry class went on a tour of the New York City Police Crime Lab. It was on that trip that Jay decided that his interest in chemistry could be best used in the field of forensic science. After his family relocated to Georgia, Jay earned his Bachelor of Science degree in Chemistry from Georgia College. To better prepare himself for a career in forensic science, Jay applied for and was accepted into the graduate program in Forensic Chemistry at the University of Pittsburgh and received his Master of Science degree in 1979. Immediately after graduate school, he was hired at the Georgia State Crime Laboratory in Atlanta.

During his 32 plus year career, Jay either performed casework in or was a supervisor for most of the forensic disciplines. Between 1982 and 1997, he wore a multitude of hats, performing casework in firearms and tool marks, hair, fiber and glass comparisons, footwear and tire tread examinations, fire debris and explosives analysis, latent fingerprint processing, marijuana identification, presumptive blood testing and crime scene analysis for a large area of central Georgia. He has testified as an expert in Federal Court and the courts of Georgia and several other states over 750 times.

 

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Jay also has extensive experience in crime laboratory accreditation, having served as an accreditation assessor and as a member of the Board of Directors of the American Society of Crime Laboratory Directors Laboratory Accreditation Board (ASCLD/LAB), including one year as the Board Chair. He has been invited to speak at seminars and training sessions on topics related to forensic science. Jay currently lives in northwest Georgia just outside the metropolitan Atlanta area, which allows him easy access to most destinations via Atlanta’s Hartsfield-Jackson International Airport.

LISTEN: http://www.blogtalkradio.com/suspensemagazine/2016/03/25/crime-and-science-radio-with-special-guest-jay-jarvis

Link goes live Saturday June 4, 2016 at 10 a.m. Pacific

LINKS:

Georgia’s Crime Doctor http://www.lulu.com/us/en/shop/jay-jarvis/georgias-crime-doctor/hardcover/product-10639368.html

Arma Forensics http://www.armaforensics.com/index.html

Crime Lab Report  http://forensicfoundations.com/crimelabreport

ASCLD/LAB http://www.ascld-lab.org

“Real-Life Not Like CSI on Television,” Macon Telegraph article on Jay Jarvis http://www.armaforensics.com/uploads/Real_Life_CSI-Grisamore.pdf

“Alumnus carries microscope into career,” Georgia College Alumnus article on Jay Jarvis

http://www.armaforensics.com/uploads/Alumnus_carries_microscope.pdf

 

Can a DNA Sample Reveal Age?

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DNA found at crime scenes can be extremely useful in identifying a perpetrator. But this only works if they have a known suspect and a DNA sample from that suspect, or if the perpetrator is in the national DNA database—-CODIS. Without something to compare the crime scene DNA sample against, DNA is not very useful. Same can be said for fingerprints. But perhaps DNA offers something else.

Employing DNA obtained from a crime scene, Familial DNA has been used to narrow the list of potential suspects and this has proven useful in many cases—such as the famous Grim Sleeper serial killer. I have blogged on this before in cases such as The Boston Strangler and the amazing case of Yara Gambirasio.

DNA will of course reveal gender, but there is also research suggesting that race, hair and eye color, and physical features such as stature might also be determined from a DNA sample. These aren’t completely worked out yet but they are intriguing aspects of DNA analysis.

But what if a DNA sample could be used to determine the approximate age of the person? This would definitely help as, once again, it would narrow the suspect list. For example, if the crime scene DNA could be shown to have come from someone who was approximately 25 years old it would effectively eliminate a 60-year-old suspect. But is this possible? Maybe.

A new approach, using a process of gene expression called methylation, seems to offer hope. Researchers at the KU Leuven University in Belgium have developed a technique for assessing the degree of methylation in a DNA sample. They believe that this analysis will narrow the age range of the individual down to a four or five year window. If this proves to be true, law enforcement will have another useful forensic science tool.

 

Guest Blogger: Lisa Black: Everything Old Is New Again

EVERYTHING OLD IS NEW AGAIN

My character, Cleveland forensic specialist Maggie Gardner, is unrealistic in one respect—she still spends a lot of time at her microscope looking at tiny bits of trace evidence, hairs, fibers, paint, and glass.

No one does that any more. Well, maybe Abby on NCIS, but she’s the most unrealistic forensic person on screen, even though she’s so cute we don’t care.

Sure, on old episodes of Dragnet you can see some nerdy guy in a lab coat explain how these pollen spores are only found in one quadrant of the city, but that art had already died before I started in forensics in 1994. We got spoiled by DNA, by ‘absolutely yes’ or ‘absolutely no’ answers. No one wanted to hear that this red nylon was ‘consistent with’ the suspect’s shirt, because they wouldn’t be hearing how many red nylon shirts were manufactured, how many were sold in this area, and while we’re at it let’s hack into Macy’s sales figures and find out who they were sold to. Unlike television, forensic labs do not have databases of all this information and would probably be violating a few important laws if they did. Nope, ‘consistent with’ was all you got. Take it or leave it.

 

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POLYURETHANE FIBERS

They left it. Microscopic analysis became more or less a thing of the past. Forensic techs today wouldn’t recognize a pollen spore or know what to do with it if they did. Fibers are ignored. Hairs are examined only to screen out candidates for, well, DNA.

Imagine my surprise, then, when I peruse the latest Journal of Forensic Sciences and stumble on an article about using something called palynological scanning to rapidly evaluate suspect and victim testimony.

 

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POLLEN

Palynology, it turns out, is a fancy name for…pollen. Pollen and spores and other ‘microscopic entities’ of trees, shrubs and herbs. No hairs, fibers or paint, but you get the idea. This analysis proved useful in some cases of rape or assault, in situations where the victim and suspect both contacted the ground and pieces of the ambient flora could attach to their clothing.

 

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In one case the suspect said he and his victim engaged on a lawn behind a public building. The victim said he attacked in a heavily wooded area, the spot surrounded by beech, birch and sycamore trees. Each site had a distinct mix of items—palynomorphs– with complicated Latin names. The suspect didn’t deny that he had made contact with the victim so willingly gave up the clothing he’d been wearing at the time, and sure enough, all those little palynomorphs indicated that he had been in the woods and not on the lawn. This did not prove that he had committed the crime. It only proved that he had lied about the sequence of events, and that was sufficient to prompt a confession. Otherwise this case would have languished in an eternal hell of ‘he said vs. she said.’

Of course had this guy listened to legal counsel before he made a statement, he probably would have figured out to come up with an alternative, and innocent, reason to have been rolling on the ground near the crime scene, and all these spores would have been for naught. As it is, surely the defense will bring out statistics regarding the vast number of beech and sycamore trees in the area, perhaps in the suspect’s own neighborhood, and the idea that maybe he had been doing some gardening earlier in the week in that same pair of pants. This is why things like pollen analysis fell out of favor with the courts…but the spores are still out there, voluminous, distinct and quite concrete little buggers that will stick in all sorts of places one might wish they wouldn’t. So are hairs, fibers, and paint. Maybe ‘consistent with’ is all you can get out of them. But maybe, sometimes, that’s enough.

So in my books Maggie still looks at all this stuff because it’s more visible and visceral than yet one more DNA sample. Let’s face it—you’ve seen one cotton swab, you’ve seen them all. Bright clothing fibers are much more entertaining.

And this trace evidence will lead her down a number of roads—some of which, it turns out, she’d be better off avoiding.

Wiltshire et al. “A Rapid and Efficient Method for Evaluation of Suspect Testimony: Palynological Screening.” Journal of Forensic Sciences, Vol. 60, #6, Nov 2015, pp 1441-1450.

 

L Black

Lisa Black has spent over 20 years in forensic science, first at the coroner’s office in Cleveland Ohio and now as a certified latent print examiner and CSI at a Florida police dept. Her books have been translated into 6 languages, one reached the NYT Bestseller’s List and one has been optioned for film and a possible TV series.

Lisa’s Website: http://www.lisa-black.com

 

that darkness cover

 

Hello! Just a quick note to let you know that my new book, That Darkness, is now available wherever books are sold!

It seemed like a typical week for crime scene specialist Maggie Gardiner–a gang boss shot in an alley, a lost girl draped over an ancient grave, a human trafficker dumped in the river–nothing all that out of the ordinary for the Cleveland police department as spring turns toward summer along the Erie banks. The methods are usual, the victims unsurprising–but when she notices a pattern, a tenuous similarity among the cases, she begins to realize that her days will never be typical again. How much of her life, her career, her friends, will she be willing to risk to do what’s right?

Jack Renner is a killer who does not kill for any of the conventional reasons…no mania, no personal demons. He simply wants to make the world a safer place. He doesn’t think of himself as a dangerous person–but he can’t let anyone stop him. Not even someone as well-meaning as Maggie Gardiner.

Maggie has the self-sufficiency of a born bit-of-a-loner. She works with a bevy of clever experts surrounded by armed police officers. She is both street smart and book smart, having seen the worst the city has to offer.

But Maggie Gardiner is not safe. And, until she can draw Jack Renner into the light, neither is anyone else.

Jeff Lindsay, author of the Dexter series, says: “Lisa Black always delivers authentic characters in riveting stories. That Darkness takes things to a spellbinding new level with a taut and haunting story that will stay with you long after you finish reading it.”

Publisher’s Weekly says: “The intriguing forensic details help drive the plot to its satisfying conclusion.”

“Black is one of the best writers of the world of forensics, and her latest introduces Maggie Gardiner, who works for the Cleveland Police Department. Her relentless pursuit of answers in a dark world of violence is both inspiring and riveting. Readers who enjoy insight into a world from an expert in the field should look no further than Black. Although Cornwell is better known, Black deserves more attention for her skillful writing – and hopefully this will be her breakout book.”– RT Book Reviews, 4 Stars (Top Pick)

 

Crime and Science Radio: Research, Education, and the Future of Forensic Science: an Interview with Dr. Katherine A. Roberts, Director of the CSULA Graduate Program in Criminalistics

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Research, Education, and the Future of Forensic Science: an Interview with Dr. Katherine A. Roberts, Director of the CSULA Graduate Program in Criminalistics

 

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BIO: Dr. Roberts is the Director of the California State University, Los Angeles Graduate Program in Criminalistics. She has served as the Director of the Master of Science degree program there since 2002,and played a leading role in the university’s FEPAC accreditation. Her research interests cover a wide array of forensic disciplines, but focus primarily of trace evidence analysis, sexual assault evidence, and mitochondrial DNA analysis. Dr. Roberts was the PI of a National Institute of Justice-funded study to investigate the use of samplematrix™ to stabilize crime scene biological samples for optimized analysis and room temperature storage from 2009-2011. She is the PI for a National Science Foundation grant that was awarded to CSULA in 2015 to establish the Center for Interdisciplinary Forensic Science Research as a research site within the NSF Industry-University Cooperative Research Center (I/UCRC) program. The Center will enhance research training and education in multiple forensic science disciplines, including Forensic Microscopy, Trace Evidence Analysis, Forensic Science Research Methods, Forensic Chemistry, and Applications of Forensic Science.

Dr. Roberts is currently collaborating with a consortium of European universities to develop a portable, inexpensive, and rapid method of dating latent fingerprints. Her publications are on topics related to trace evidence analysis, forensic examination of sexual assault evidence, and mitochondrial DNA analysis.

She was an elected member of the Technical Working Group for Education and Training in Forensic Science (TWGED) that was convened by the National Institute of Justice. The Forensic Science Education Programs Accreditation Commission (FEPAC) uses the report issued by TWGED in order to evaluate the academic standards of undergraduate and graduate forensic science programs.

Dr. Roberts is currently serving as the  Interim Executive Director of the California Forensic Science Institute.

Education

PhD     Forensic Science, Graduate School & University

Center, City University New York

M.Phil  Criminal Justice, Graduate School & University

Center, City University New York

MSc     Forensic Science, University of Strathclyde, Glasgow

BSc     Chemistry, King’s College, University of London

 

LISTEN: Link Goes Live Saturday 3-26-16 10 a.m. Pacific http://www.blogtalkradio.com/suspensemagazine/2016/02/23/crime-and-science-radio-with-special-guest-dr-katherine-roberts

 

LINKS: California Forensic Science Institute http://www.calstatela.edu/hhs/cfsi

CSULA School of Criminal Justice and Criminalistics http://www.calstatela.edu/hhs/crim

LA Times article, “Cal State L.A. graduate students hone crime scene expertise,” http://articles.latimes.com/2013/jul/27/local/la-me-cal-state-criminalists-20130728

Forensic Science Education Programs Accreditation Commission (FEPAC) http://www.fepac-edu.org

 
 
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