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Category Archives: High Tech Forensics

Can Odor Reveal the Time Of Death?

One of the most important determinations that the medical examiner must make in any death investigation is the Time Of Death (TOD). This alone might help solve a homicide. Who had the motive, means, and opportunity? The time of death relates to the opportunity. If the death occurred while the primary suspect was in another state or had a solid alibi, then he moves down the suspect list. On the other hand, if the TOD was determined to be a time frame where he was in the neighborhood, then he remains a viable suspect.

The ME uses many techniques to help estimate the TOD. Check out this ARTICLE for a brief overview of these techniques. One of the methods he employs is the degree of decay that has occurred. He must take into account the environmental conditions near the corpse and then must make a best estimate as to how fast the decomposition process would have advanced under those conditions. This is always a best guess, as is the case with each of the techniques he employs.

When a corpse decays it undergoes a chemical decomposition and this process releases many volatile organic compounds (VOCs) into the surrounding air. These compounds are at least partially responsible for the odor of decay and they tend to be released in a predictable pattern as the decay process progresses. What if these VOCs could be sampled and used as a more scientific method for determining the Post Mortem Interval (PMI)? That is, the time since death.

Research is currently underway to assess this technique. Using the combination of gas chromatography and mass spectrometry (GC/MS), researchers have found that these volatile chemicals can be trapped and analyzed. Hopefully this technique will prove to be useful in narrowing down the TOD. We’ll see.

 

Gas Chromatograph

Gas Chromatograph

 

 

 

Futuristic Robotic Surgery Is Here

Robotic Device

 

My second Dub Walker thriller HOT LIGHTS, COLD STEEL dealt with the future of robotic surgery. Future as in way down the road. But now it seems it’s not all that far away. Virtual Incision in Lincoln, Nebraska is working on a very clever device that could make space missions safer. Very cool stuff.

 

HLCSCover300X450

 

Guest Blogger: Ronnie Custer: Cyber Crime: Time To Update International Laws?

Cybercrime

 

 

Universal Law against Cyber Crime Is What We Need

How are cyber crimes perpetuated?

There are many ways in which cyber crimes are perpetrated and technologically savvy attackers are indeed inventing newer ones to outwit law enforcement too. However, the main kind is as follows:

1. Unauthorized or unsolicited access to computer systems or networks with malicious intentions     or motives also termed hacking

2. Data theft of electronically stored information

3. Stratified e-mail bombardment

4. Manipulating electronic data before and after processing

5. Salami attacks mostly on financial and economic data

6. Denial of Service Attacks

7. Virus or worm attacks

8. Trojan Horse or data infiltration to cause damages, or suspension of services

How are they detected? 

Usually, cyber crimes are detected when the individual or institution notices large sums of money are unreasonably withdrawn from their accounts, or their system has become corrupted or malfunctioning. Complaints filed with the relevant Cyber Cell Departments or law enforcement are also ways of detection such genre of crimes. Many new anti cyber crime technology, tools and softwares are now being provided and installed which are able to detect cyber crimes sometimes even before the real damage sets in. Anti Virus Software (AVS) and other lingering software in computer systems are able to detect and resolve many instances of illegal entry.

Universal laws and not country- specific laws are the need of hour for addressing cyber crimes: 

Another major reason why there needs to be universal laws against cyber crimes is that there may be some different sets of cyber laws enacted and enforced by different countries of the world. While the EU may have one set of laws, the Middle East may have another and the Far East yet another, with the Americas, distinguishing itself with the fourth set of different regulatory regimes regarding cybercrimes and its treatment. Thus, enforcement of laws and bringing culprits or perpetrators before the due process of law would be a very difficult proposition, especially if this is of trans border kind with many conflicting enactment, laws and procedures. With country specific laws, it is also difficult to agree on which laws the violators could be tried and punished- the laws of the cyber crime perpetrating country, the laws of the victim’s country or the preponderance of global laws since the crimes were committed  on global internet highway.

There is every possibility that with nebulous laws, the perpetrators could stand good chance of going scot free, due to lack of evidence and even lack of law enforcement techniques.

But if there is preponderance of global set of cyber security laws and their enforcement, there is every likelihood that perpetrators would be made to stand trial and pay for their crimes.

Reasons for apparent need for globally enforceable, universal anti cyber crime 

¬ Changes in global, regional and domestic demographics have indeed warranted the need and urgency for universal laws to combat cyber crimes. Governments of various nations of the world, even involving the Interpol needs to be placed at the disposal of cyber crime fighters, wherever and whenever necessary to do so.

¬ Dramatic and major developments in online communications have indeed aided and abetted cyber criminals, some of whom may be masters of the cyber crime business. They regularly outwit law enforcing agencies and many global cyber crimes remain unsolved to this day due to lack of needed evidence and enforcement laws

¬ Since cyber crimes are now not bound to one country or state, encompassing, as it were, several States and nations through globalization, it has become imperative for States to act together and work in much closer manner to control menace of cyber crime and its after effects, on individuals, cohorts, agencies, institutions and governments. This could indeed be greater advantageous if there is a consistent, cohesive and solid set of Universal laws to which all signing countries need to adhere, abide and to enforce in a consistent, comparable and cohesive manner.

¬ Criminals do take advantage of weak and inconsistent laws to wreck havoc with apparent impunity. They know that current laws are insufficient to indict or even charge them. Global law enforcement with strong legal armory could indeed stop many varieties of online crimes dead on their tracks

Conclusion: Global cyber crime can only be effectively apprehended, prosecuted and eradicated if all nations of the world join together in a determined manner to try and wipe out this scourge from the face of the earth through Universal laws, that act and impact on every nation on earth which is in dire need of robust anti cyber crime fighting mechanism.

Author Bio: I am Ronnie Custer and I am intended on writing academic cases for the past several years that are assisted me to gain knowledge in writing grading assignments for all sorts of students. I have worked in different companies in writing industry.

Links for further reading:

FBI Cyber Crime: http://www.fbi.gov/about-us/investigate/cyber

Computer Crime, Wikipedia: http://en.wikipedia.org/wiki/Computer_crime

Cybercrime: Is It Out of Control?: http://www.theguardian.com/technology/2011/sep/21/cybercrime-spam-phishing-viruses-malware

James Lynn on TED: Everyday Cybercrime: http://www.ted.com/talks/james_lyne_everyday_cybercrime_and_what_you_can_do_about_it

 

 

Do Identical Twins Have Different DNA?

twins-1

 

DNA profiling is considered the gold standard for individual identification. DNA-containing bodily fluids found at crime scenes can often be linked to the perpetrator with a high degree of accuracy, often measured in one per billions. It is highly individual and therefore highly accurate for identifying a given individual.

But since identical twins begin as the same fertilized egg, they have identical genetic material (DNA). After fertilization, the fertilized egg divides into two cells. To produce identical twins, these two cells separate and then each progresses forward to produce an individual. This results in two identical individuals with identical DNA. Or does it?

Twins egg:sperm

 

Standard DNA testing uses the concept of Short Tandem Repeats (STR’s). STR’s are simply short segments of DNA that repeat in certain areas of the very long DNA strand found in all of us. The number of these repeats in the various locations are what allow DNA profiling to distinguish individuals so accurately. This is a complex, though not really difficult to understand, technique which is discussed in great detail in two of my books: Forensics For Dummies and Howdunnit: Forensics.

DNA Profile

But scientists have known for years that the DNA of identical twins is not perfectly identical. It might or might not start out that way at that first cell division but for sure as the cells divide and the individual grows within the uterus, minor DNA changes can occur. These are on the level of the base pair sequences that make up the DNA chain.

Another DNA technique called Single Nucleotide Polymorphism (SNP) actually looks at each base in the DNA strand and uses this for comparison with another strand to determine if they came from the same individual. This is the direction that DNA testing is going but for now STR remains the method of choice.

Identical twins would look the same using STR analysis but a deeper analysis using SNP would reveal variations, thus allowing identification and separation of two identical twins. Let’s say, blood is left at a crime scene and that blood is matched to a particular individual. Let’s further say that this individual is an identical twin. STR DNA analysis would not distinguish between these two brothers, But if SNP is employed, the one who left the blood at the scene can be distinguished from his identical twin.

The recent French serial rape investigation involving identical twins Yohan and Elwin would be a case in point. Applying the SNP technique in this situation would likely solve the case.

Pretty cool stuff.

Howdunnit Forensics Cover

 

From HOWDUNNIT: FORENSICS:

SINGLE NUCLEOTIDE POLYMORPHISM

Single nucleotide polymorphism (SNP) is a new technique that will likely see increased use in the future. The major problem at present is that it is expensive. We saw that RFLP fragments were fairly long, a drawback that lessens their value in degraded or damaged samples (discussed later). This problem was circumvented by the discovery of STRs, which are very short fragments. But, what if the DNA examiner could use single nucleotide bases as the standard for matching? This would increase the discriminatory power of DNA even further. This is what SNP does.

Let’s say that two sequenced DNA strands looked like this:

CGATTACAGGATTA and CGATTACAAGATTA

If we searched for an “ATTA” STR repeat, these two strands would be indistinguishable

since both have two ATTA repeats. But, with single nucleotide analysis the strands differ by a single base: The ninth base in the first sequence is guanine (G), while it is adenine (A) in the second one. SNP can be used with restriction enzymes in the RFLP technique, or with PCR, where it can be easily automated. Theoretically, this will allow for discriminating two DNA samples based on a single nucleotide difference.

 

Eyes of the Beholder: An Old Myth Resurfaces, Sort Of.

eye-reflection

A century ago it was widely believed that the image of a killer was forever imprinted in the eyes of the victim. Sort of stamped on their retinas. This has been termed Optography and was a fiction staple in the 1800s and early 1900s. Of course, this isn’t the case. Not possible. Not yet, anyway but who knows what the future will hold.

However, in some situations a photo of the victim just might retain the killer’s image and this might be useful in tracking down the bad guy.

 

Undetectable 3D Printed Gun

3D Printed Gun

 

 

Airport security uses low level x-rays and metal detection. But will it detect a plastic gun? Like one that can be printed using the 3D printing technology?

 

3D Printer

3D Printer

 

 

Such a gun was predicted many years ago in Frederick Forsyth’s classic The Day of the Jackal. The original 1973 movie version anyway. The Jackal not only had that cool rifle disguised as crutches, but also a double-barreled handgun that was plastic and fired plastic bullets, if I remember correctly. Been a while since I saw the movie.

 

day of jackal

 

Bloodstain Camera Finds Blood Quickly and Efficiently

Detecting blood at a crime scene is often essential for determining if a crime did indeed occur and how the act unfolded—crime scene reconstruction. At the scene, a meticulous search for blood can be tedious, time-consuming, and eat up many man-hours.

 

Techs search for bloodstains

Techs search for bloodstains

 

Shed blood is not always obvious. The stains are not always patent (visible) but rather latent (invisible). The standard in such situations has been to employ Luminol, which can find even very small latent bloodstains. But Luminol takes time and requires darkness—not always obtainable, particularly in outdoor, daytime crime scenes.

 

Luminol helps expose latent bloody shoeprints

Luminol helps expose latent bloody shoeprints

 

A new technology developed by Dr. Meez Islam and colleagues at Teeside University promises to not only be able to detect latent blood spatters quickly but also age the blood very accurately. With month-old stains the device, which uses hyperspectral imaging, can narrow its deposition down to a day and with fresh blood down to an hour. This should greatly help with Time of Death determination—-or at least the time when the blood was shed.

 

Fresh blood spatter

Fresh blood spatter

 

Blood exits the body bright red but with time and oxidation becomes rusty brown and does so along a predictable timeline. Accurate determination of the bloodstain’s color with hyperspectral imaging reveals its approximate age.

Very cool. And potentially very useful.

 

Ten Most Common Forensic Mistakes in Fiction

Ten Most Common Forensic Mistakes in Fiction: A fun Big Thrill interview with Jan Burke and I:

http://www.thebigthrill.org/2013/10/special-to-the-big-thrill-10-most-common-mistakes-in-fiction-regarding-forensics-by-d-p-lyle-jan-burke/

 

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.

breathprinting_l

 

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.

 

DNA in a NY Minute

DNA Analyzer

 

Writers often send me questions about DNA, and most include something about the turn around time for DNA analysis. Ten years ago the answer was weeks, five years ago hours, and now it seems only minutes are required.

Engineers at the University of Washington and scientists at NanoFracture, a company in Bellevue, WA, have developed a DNA extractor that uses electrodes and not spinning centrifuges to perform the critical and time-consuming step of removing DNA from any body fluid. And it does so in only a couple of minutes. Then on to a sequencer and before you know it you have a DNA profile.

Though not commercially available yet, this technology exists and it will be interesting to see how it progresses. Of course, it’s fiction-ready right now.

 
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Posted by on June 4, 2013 in DNA, High Tech Forensics

 
 
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