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Monthly Archives: November 2010

Blood Camera: The New Luminol?

The most important material that investigators can find a crime scene is blood. It tells them a great deal. Blood is both a biological and a physical material. That is it has biological properties but it also behaves as a liquid. Employing both of these characteristics can be of great benefit to investigators.

Blood typing and DNA are usually readily done on crime scene samples unless they are so degraded that this type of testing is not possible. That is not often the case. Blood type and DNA can exclude some people and point the finger directly at others.

Blood behaving as a liquid can reveal to investigators how the crime occurred. Did the blood simply leak from a wound or did it spray from an arterial injury? Was it spattered as the result of a gunshot or blows to the head from a baseball bat? Did the victim standstill, lie on the floor, or walk or run away after the injury? The blood splatter pattern can reveal what happened and often where the various players in the crime were at the time the blood was shed. This can support or refute suspect and witness statements.

Often a killer will attempt to clean up a crime scene and scrub away the victim’s blood hoping that there will be no evidence of the crime remaining. Most of you are familiar with Luminol which has been employed in such cases. When properly used it can reveal blood splatter patterns even after the scene has been cleaned and indeed will often show the swipes and scrubs left behind by the cleaning utensil. It is highly sensitive and will find blood in the parts per billion.

Using Luminol requires that the area be sprayed with Luminol solution and then the room must be darkened and viewed using UV light. This can sometimes be cumbersome, particularly when attempting to evaluate a scene during the daytime. The windows in the room must be covered and all sources of light must be blocked out to get the best effect.

Add to this the fact that many other substances such as bleach, coffee, and rust can interfere with Luminol testing. Luminol can also damage the blood so that DNA testing will be less accurate.

Now it seems that a camera has been developed that will do the work of Luminol. It apparently uses pulses of infrared light and then measures the light reflected back to the camera. It filters out unwanted light wavelengths and concentrates on those consistent with blood proteins.

This is a very clever tool and hopefully it will work out to be as useful as it seems to be.

 
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Posted by on November 29, 2010 in Blood Analysis, High Tech Forensics

 

Estimating Age From Crime Scene Blood

The police are called to a suspected crime scene, one where a murder has likely taken place. There is no body. There is no suspect. There are no witnesses. But a large blood stain is found at the scene. Whose blood is it?


Any police investigator will tell you that identifying victim is one of the first and most important steps in identifying the perpetrator. The simple reason is that most murders are committed by someone with some relationship to victim. A spouse, a friend, a coworker. But without a corpse, how can the victim be identified?

Since in this circumstance there would be no description of victim, the police would not know where to look. They would have no age, sex, size and weight, height, or any of the other physical details that might narrow their search for who the victim might be. Each one of these factors can help narrow the possibilities.

But what if they could determine that the victim was a teenager or a middle-aged male or an elderly female? DNA obtained from the blood could easily determine the sex but not the age of the victim. Until now. There appears to be a new test that just might reveal age from a crime scene blood sample. And least in broad terms.

A recent report in the journal Current Biology submitted by researchers from the Erasmus MC University Medical Center in Rotterdam, Netherlands suggests that byproducts from human T cells might supply this information. It’s complex biology but it seems that our T cells, which are an important component of our immune system, have great diversity in their receptors. It is these receptors that allow them to recognize a multitude of foreign invaders and tag them for destruction by the white blood cells and other components in the complex system that protects us from infections.

It seems that this diversity is accomplished through a constant rearrangement of the DNA within the T cells. A byproduct of this process is the creation of small circular DNA molecules known as Signal Joint TCR Excision Circles, or sjTRECs for short. It appears that the amount of these DNA packets declines at a constant rate with age. Using them, these researchers believe that they can narrow the age range of the person who shed the blood to within 20 years. Not very accurate but it would distinguish a teenager from a middle-aged person or an elderly individual and this in turn might help identify the victim.

Stay tuned. This could prove to be an interesting and useful technique. Or not.

 

Angel of Death By Proxy?

Most of you have heard of Munchausen Syndrome. It is an odd psychiatric disorder where the person harms themselves or makes themselves ill in order to receive medical care. The payoff seems to be the attention they receive from being the victim of some dread illness or injury. These people will subject themselves to all sorts of medical testing, including some that are dangerous and painful.

A subform of this is called Munchausen By Proxy. In this case the victim is not the person with the mental disturbance but rather someone else. Typically a parent will harm or make ill a child so that the child requires medical care. The payoff is that the parent gets to play victim and receive all the sympathy and attention that goes along with being the co-victim of the disease process or injury. In this case it is the child that is subjected to needless and often dangerous and painful medical procedures.

You’ve also no doubt heard the term Angel of Death. Traditionally this term is applied to nurses, but it can also be applied to doctors and other healthcare personnel, who kill patients as part of some deep psychopathological disturbance. They are often the most dangerous of serial killers simply because they have plenty of ready victims and several methods for doing them in. People die in the hospital all the time so a few extra deaths can go unnoticed for many years and even decades. For tis reason, many of these are among our most prolific serial killers.

But what if one of these Angels decided to do their deeds by proxy? What if they could convince someone else to take their own life? What if there psychopathology was fed by this serial killing by proxy? A pretty disturbing circumstance.

But that may very well be the case with William Melchert-Dinkel. At least this is what prosecutors in Faribault, Minnesota believe. Mr. Melchert-Dinkel has pled not guilty to the charges and the investigation is ongoing but prosecutors believe that Melchert-Dinkel posed as a young female nurse on the Internet and offered sympathy, support, and instructions on how to commit suicide to at least two stressed and depressed people. One a 32-year-old male in Coventry, England and the other an 18-year-old girl in Brampton, Ontario.

Could this be a case of Angel of Death by Proxy?

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Guest Blogger: The French Ripper and the Brilliant Pathologist by Katherine Ramsland

As forensic science was getting a foothold during the 19th century, pathologists worked under tough conditions. Among the fascinating items that science journalist Douglas Starr includes in his new book, The Killer of Little Shepherds (Knopf), are the innovations they used to make their workspace – the corpse – tolerable for an autopsy. For example, bacteria that colonized a decomposing body produced fetid gases, so Paul Brouardel devised a way to clear them out: he would prick the body with numerous small holes and light the escaping gasses. This produced a series of fine blue jets that burned for days. When they disappeared, Brouardel knew he could safely proceed.

As a historian of forensic science and psychology, I’m always happy to find a well-researched book on the subject, and Starr has exhaustively explored the activities and contributions of one of my favorite forensic scientists, French criminalist Alexandre Lacassagne. For context, Starr lays out the crime spree of an infamous serial killer, Joseph Vacher, whom journalists likened to London’s Jack the Ripper.  For authentic material, Starr had perused the files and met the descendants of the nineteenth century’s greatest pathologist, and years or research he’s produced a gripping tale. In addition, he brings attention to just how much the forensic scientists of today resemble their forerunners. “Theirs was the first generation of modern criminologists,” Starr writes, “ and they developed the techniques that characterize forensic science to this day.”

Vacher and Lacassagne

Lacassagne was one of the top innovators in Europe, as he approached crime scenes with a healthy sense of doubt. Too often he saw the effects of investigative tunnel vision that led to hasty resolutions that ruined innocent lives. Like forensic scientists today, Lacassagne and his colleagues were concerned about hired guns on the witness stand, the presentation of scientific material to uneducated juries, the best way to handle evidence, and using the most advanced knowledge and techniques. He kept on eye out for improving conditions and supporting justice.

 

Vacher Crime Scene Sketches:

 

Years before the publication of the first story featuring Sherlock Holmes, Lacassagne exercised full critical examination of the cases on which he consulted. When he suspected that a suicide was actually a staged homicide, for example, he asked colleagues to tell him immediately of recent deaths so he could see whether he could get the decedent’s hand to grip an object as tightly as the “suicide victim” had clutched a gun. A dead hand, he learned, could be positioned to form a loose grip, which tightened with rigor mortis. This weakened the determination of suicide, and with other suspicious factors, it inspired the police to re-open the case. They arrested the victim’s son for murder.

Due to his careful work, prestigious university position and authoritative bearing, Lacassagne became a celebrity consultant. Although his most memorable contributions were in pathology and criminalistics, I was most interested in his innovations for criminology. Lacassagne instigated the earliest criminal autobiographies, encouraging many inmates at Saint-Paul prison to write about themselves. Each week he checked their notebooks, correcting and guiding these men and women toward some revealed insight. Their family histories were full of violence, tension, and disease, which taught him a great deal about the origins and influences of criminality. However, he had no sympathy for malingerers.

Enter Vacher, arrested in 1897. Starr ably alternates his story with Lacassagne’s until they merge for Vacher’s pre-trial assessment. Vacher had terrorized the countryside, picking victims at random for bludgeoning, strangling, and mutilation. Despite how geographically far apart these cases were, common patterns alerted an astute magistrate to the possibility of a single offender. Thus, the country went on high alert. Vacher, a roaming vagabond, confessed to eleven murders, but he was suspected of many more. In his defense, he claimed to suffer from an irresistible impulse.  Having been bitten by a rabid dog when he was a child, he insisted that his blood had been poisoned. His defense team believed his claim of madness.

Lacassagne was the lead examining physician for the prosecution, and he spent five months learning about Vacher’s background, supposed spells of temporary insanity, persecution mania, and trail of violence. In the trial, Lacassagne took the stand in an unruly courtroom, where Vacher shouted at witnesses and challenged anyone who did not believe him. (The courtroom scenes alone make this book worth reading.) Starr presents Lacassagne’s philosophy about the role and demeanor of an expert witness (including how to dress) and shows how the pathologist carefully laid out his opinion to a breathless audience. He’d even made his own crime scene sketches. Even Vacher was impressed.

Lacassagne once said, “Societies have the criminals they deserve.”  While he believed that disease and addiction, passed on to successive generations, could cause mental and physical degeneracy, he thought that poverty, social marginalization, and other factors were also involved. “The criminal is a microbe,” he said, “that proliferates only in a certain environment.”  Still, he knew that psychosis could be faked, and he found Vacher to be a “sanguinary sadist,” i.e., a calculating, bloodthirsty psychopath.

Starr gives both men so much life and dimension that readers will feel as if they’re right there in the courtroom, awaiting the outcome. Vacher holds his own as a belligerent and grandiose serial killer, which provides plenty of tension for the adversarial arena. This book is a must-read for anyone who likes tales about intelligent investigators matching wits against wily offenders. Along the way, you’ll also learn a lot about the birth of forensic science.

Katherine Ramsland, Ph.D., holds graduate degrees in forensic psychology, clinical psychology, and philosophy. Currently, she chairs the Social Sciences Department and teaches forensic psychology and criminal justice at DeSales University in Pennsylvania. She has published over 900 articles and thirty-seven books, including The Forensic Psychology of Criminal Minds, True Stories of CSI, Beating the Devil’s Game: A History of Forensic Science and Criminal Investigation, The Human Predator: A Historical Chronicle of Serial Murder and Forensic Investigation, The CSI Effect, Inside the Minds of Serial Killers, Inside the Minds of Healthcare Serial Killers, Inside the Minds of Sexual Predators, and Inside the Minds of Mass Murderers. She has been published in ten languages. Her background in forensic studies positioned her to assist former FBI profiler John Douglas on his book, The Cases that Haunt Us, to co-write a book with former FBI profiler, Gregg McCrary, The Unknown Darkness, and to collaborate on A Voice for the Dead with attorney James E. Starrs on his exhumation projects and on a forensic textbook with renowned criminalist Henry C. Lee, The Real World of a Forensic Scientist. She also published The Forensic Science of CSI, The Criminal Mind: A Writer’s Guide to Forensic Psychology, and The Science of Cold Case Files, and has written numerous editorials on breaking forensic cases for The Philadelphia Inquirer. For seven years, she contributed regularly to Court TV’s Crime Library, and now writes a column on historic forensics for The Forensic Examiner, offers cases analysis for the media and speaks internationally about forensic psychology, forensic science, and serial murder. She has appeared on numerous cable network documentaries, as well as such programs as The Today Show, 20/20, Montel Williams, NPR, Larry King Live and E! True Hollywood.

Visit Katherine’s Website

 

Q and A: Lily of the Valley Poisoning

Q: In my novel an 82 year old woman is found dead. Lily of the Valley, ground up and put in her loose tea, is what I’m using as a poison. How much should the dosage be and how will the ME find it?

B. Giersch

A: Lilly of the Valley (Convallaria majalias) is native to Canada and the Mid-West and Western US. All parts of the plane are toxic, particularly the leaves. Water in which the cut flowers have been kept is also toxic. Though the water may yield enough toxin to be deadly, a “tea” made by boiling the leaves, would certainly contain even more of the toxin and would be a more effective poison.

LILY OF THE VALLEY

The toxin in Lilly of the Valley is called convallatoxin. It is a glycoside in the same family as digitalis, which comes from the Foxglove (Digitalis purpurea or D. lanata).

FOXGLOVE

 

How many leaves would your killer have to crumble and mix with the tea? There is no way to tell. Each plant contains a different amount of the toxin so the leaves would vary greatly in their potency. The actual amount of toxin in a teaspoon of crumbled leaves is guess work at best. This is good since you can add almost any amount and be OK. Or simply skip theamountand let the reader assume the killer added enough.

Symptoms onset quickly and include nausea, vomiting, abdominal pain, flushing, hot flashes, dilated (enlarged) pupils, a red skin rash, excessive salivation, coma, and death. These glycosides can also cause deadly alterations in cardiac rhythm, which can lead to sudden collapse and death.

A toxicological examination of the blood, urine, and stomach contents would easily uncover the toxin since glycosides are easily identified. Initially the toxicologist might only be able to say that the blood contained a glycoside but not which one. Digitalis? Convallatoxin? Further testing with gas chromatography and mass spectroscopy (GC/MS) would determine which glycoside was present and would expose the actual cause of death.

 
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Posted by on November 15, 2010 in Poisons & Drugs, Q&A

 

Astronauts, Postmenopausal Women, and Brittle Bones

It’s well known that as we age our bones demineralize, or lose calcium, and become weaker and more prone to fractures. This seems to be particularly true in postmenopausal women where it has to do with the loss of hormonal support for bone matrix development and calcium deposition. This is often a difficult problem and treatment is also problematic. Most physicians recommend calcium, vitamin D, and exercise. Weight bearing exercise is important because it helps prevent mineral loss and keeps the bones strong. It’s similar to building muscles through weight lifting. You must stress the muscles in order for them to increase in size and strength. The same goes for bones.

Bone and mineral loss is also a major problem with astronauts who spend months in weightlessness. If there is no stress on the bones, they begin to lose calcium and become weaker. It has been estimated that an astronaut will lose the same amount of calcium and bone strength in one month than a postmenopausal woman would lose in one year.

How do you get around this? Weightlifting in space simply will not work because the weights are weightless. No resistance, no improvement in bone strength and mineralization. To get around this astronauts have used bungee cords and other elastic devices to add that resistance and keep their muscles and bones strong. The Russians at one time devised a suit with bungee cords built-in but it proved to be cumbersome to use in the confines of the International Space Station (ISS).

Leave it to those guys at the Massachusetts Institute of Technology (MIT) to come up with a clever solution. They have developed a sort of Spider Man suit made of a stretchy elastic material that forces exertion with the movement of arms and legs. This resistance helps keep the astronauts’ muscle and bone strength intact during those long months in space.

 
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Posted by on November 11, 2010 in Medical Issues, Space Program

 

Q & A: What Kidney Disease Might Cause My Character to Need a Transplant?

Q: I need a kidney disorder that over a period of a year or so will require a transplant.  The character is a 55-year-old woman who has only one functioning kidney due to a congenital defect. I’d like her symptoms to be mild at first, then progressively worsen so that she must be on dialysis to survive until a donor can be found. What condition might fit this scenario?  What would the symptoms be? How long would her recovery be after the transplant?

Karen Sandler
www.karensandler.net

 

A: Virtually any kidney disorder can progress to what we call Chronic Renal Failure (CRF for short). This is where the kidneys are so damaged that they no longer clean the blood, which, along with excreting of water, is their primary function. This can be mild to severe. Many people with CRF rock along for years before function declines to the point that dialysis and/or renal transplant are needed. This is highly variable from person to person and from underlying condition to underlying condition. This means that your character could have CRF for a few months or a decade or so and anywhere in between before either dialysis or transplant entered the picture.

 

Common underlying causes of CRF are high blood pressure (hypertension or HBP), Diabetes, Glomerulonephritis (comes in many types and as a group are processes that inflame and damage the kidneys), many of the so-called autoimmune diseases (Lupus, Scleraderma, Dermatomyositis, Rheumatoid Arthritis, and others), and many other illnesses. A common congenital problem that would work for you would be Polycystic Kidney Disease where the kidneys are gradually damaged as cysts develop and grow within the kidneys. Your character could easily lose one kidney to this and then have the other one fail as the disease progresses. CRF in this entity can begin at almost any age.

The symptoms of CRF vary depending on the underlying cause. In general, CRF causes fatigue, poor appetite, weight loss, and edema of the feet and hands as fluid accumulates in the body. When CRF becomes severe, added symptoms could be shortness of breath, sleepiness, confusion, disorientation, coma, and death. Dialysis is used until a suitable kidney donor is located.

Recovery from the transplant is similar to any other abdominal surgery. Four or five days to a week or so in the hospital, a few weeks of reduced activity and then by about 6 to 10 weeks she would be back to normal. This all assumes that the transplant was successful, that there was no rejection, and that her kidney function returned to normal or nearly so fairly quickly after surgery.

 
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Posted by on November 8, 2010 in Medical Issues, Q&A

 

DNA Mist Can Track Robbers

Every now and then you run across something that is so simple, yet so ingenious, that you just shake your head. This one makes you wonder why they didn’t think of it before.

You know those little explosive dye packets they place in the money bag that tellers hand to criminals during a robbery? When they open the bag it explodes and anyone nearby is painted with indelible ink? Those are cool, but this new technique is even better.

It seems that those clever folks in the Netherlands have come up with a DNA spray that is mounted near the door of a bank or other business. It is triggered by the teller or a store employee. The fine mist that is released has no odor and is completely unnoticeable, yet attaches to everyone who passes through it. It settles into their hair, clothing, and on any exposed body parts without the perpetrator knowing what has happened.

 

The Spritzer

The spray contains a synthetic DNA that is apparently marked with a fluorescent marker that makes it visible under ultraviolet light. The DNA can then be sampled and sequenced. The DNA fingerprint obtained from the robber can be linked to the DNA assigned to that particular location since each has its own specific profile.

Very cool and clever.

 
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Posted by on November 2, 2010 in DNA, High Tech Forensics, Police Procedure

 
 
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