Showing posts with label CSI. Show all posts
Showing posts with label CSI. Show all posts

Sunday, March 27, 2016

Helping You Write a Killer Plot - an Interview with a CSI and Death Investigator

Fiona - 
In this article, we will be visiting with Karen Sue Lind who is a certified CSI.  

Karen Sue, can you introduce yourself to us? I'm wondering what brought you to this career and what types of personalities would flourish doing CSI work.

Karen Sue - 
I grew up a mystery fan and read all the Nancy Drew and Trixie Beldon books I could find. When I was 13, a good friend was kidnapped and killed by the serial killer William Bonin, known as the "Orange County Freeway Killer". The loss and quest to understand is what drove my interest in forensics.

I studied Crime Scene Investigation, and Crime Analysis at University of Riverside, California and am a certified Crime Scene Investigator.  


I also have extensive training in collecting and preserving entomology (go HERE for crime scene bug info) specimens having trained under Dr. Neil Haskell. 

I spent 3 years performing autopsies, x-rays, and fingerprint work before promoting to investigator. My official title was Deputy Coroner. It is a sworn and armed position with limited peace officer powers allowing me to protect myself and my crime scene when needed. I spent 8 years in that position, and was a training officer as well. I averaged about 300 cases a year, and that included all types of deaths.



It takes a special kind of person to do my job. The television shows do not, and probably could not, show what it actually does to the soul and the mind. Besides being very gross at times, it is very emotionally draining, and you cannot clear your mind of the things you see.


Fiona - 
Can you talk about that for a moment? On TV, in movies, in books even (where there's a better opportunity to show the dark and the light in a character), the CSI and others on scene are just doing their job; but as psychology advances, we know that there is an enormous price that an individual pays. What systems did you put in place to help you survive doing this very important job?

Karen Sue - 
To do this job, it takes someone with a strong sense of survival. It can be dangerous in the field, and you have to be street smart.

My husband is in his 29th year in law enforcement. I knew that I was not meant to be a cop, but he introduced me to the field of forensics at a civilian level and I went back to school when the kids were older. To survive as a cop's wife, you have to have a strong personality because they are not always available. There is a lot of worry when you have a spouse out there on the street and it makes you stronger.

For some reason my husband and I have known many friends and family who have died unexpectedly or tragically. That has also made me stronger. I have a strong will to survive. I also know what it is like to lose someone close and have so many questions about what happened. It is my desire to help others understand what has happened to their loved ones. That drove me to be the person who helps them find out.

This job is not for everyone. I have heard stories of people who hired onto the coroner's office and not even last past lunch. Some cannot take the gore of the job and others cannot take the emotional pain it inflicts.

Fiona - 
Did you have self-care routines in place? Yoga? Walks alone in the woods? -- Wait, that might spark some distress . . .

Karen Sue -
I am fortunate that my husband as well as several friends, and family members work in related fields so I can talk to them about bad cases and they can understand and support me without me having to go into detail. I also have a couple rescue dogs that are now registered as my emotional support dogs. When I would have a bad day and come home emotionally drained, just interacting with these loving, giving creatures would give me peace and comfort me because they need no details and no explanation.

In the beginning when I first started doing the job, I found myself drawn to watching birthing shows. My husband asked me what was causing me to watch all these shows about babies! I said I think somewhere in my head I am trying to balance all of the death with new innocent life!

I also have multiple hobbies of reading, crafting, and gardening.

Fiona - 
What a beautiful image of you balancing the death and new life. Thank you for that - and don't be surprised if it shows up in one of my books. It's very poignant.

You mentioned dangers in your job and needing street smarts. Can you tell us more about this? In my fictional and research contact with crime scenes, the crime is over and the CSI comes in and does their job. But your answer tells me that you have to both be gathering evidence and looking over your shoulder - do you have an officer guarding you as you work?

Karen Sue - 

In the department that I worked for, we were sworn with limited peace officer powers. We had the option of wearing plain clothes or a complete uniform. Either way, we were always armed. 

I received training in hand to hand self defense. My utility or duty belt (go HERE to learn about a  duty belt) included a baton, pepper spray, handcuffs, and of course my firearm. 

I had quarterly firearm qualifications just as the fully sworn deputies did. I can shoot with either hand, though not at the same level! of course!

Because I investigated all types of deaths, I was in a variety of situations. I also was responsible for notifying the family of the death. (For information about death notification, go HERE) I have been at homicide scenes where the suspect was unknown, and could be one of the family members I had to speak with. I have been at scenes where gang members returned to boast their kill, and the victims gang was waiting as well.

The most dangerous part, where the street smarts come in, would be with notifications. The family members of ex convicts and drug dealers also die, and we are still obligated to find them and notify them the same as anyone else. I worked alone and often found myself in bad neighborhoods in the middle of the night, knocking on doors.

When you knock on the door of a drug dealer at 2 am, and announce Sheriff's office, they do not think you are there to tell them their mother has been in a car accident. They think you are trying to bust them and do not handle it well. I have had to be quick with my words to keep the situation calm and focused.

Also, family members often react badly when they learn of a loved ones death. I have had family members start accusing each other and get physical with each other right in front of me and had to calm them all down with "verbal judo" as I was out numbered and knew drawing one of my weapons would only make it worse. When I got their attention I was able to calm them to the point they apologized to ME! That is where the street smarts and being quick can make the difference between walking out of a scene or becoming a victim as well.

Fiona - 
How did you move from CSI to death investigator? Was that a career path you sought out?

Karen Sue - 
I actually wanted to go into profiling, and started taking classes in that field. The college then began a brand new CSI program, and I added those classes. I was one of the first to complete the certification. My belief was the more knowledge the better. One day my husband learned of an entry level position at the Coroner's unit and suggested I apply to "get my foot in the door". As part of their screening process I had to go there for a day to interact and observe autopsies. Once I was able to look into a body and hold a lung I was hooked!!!

Of course all of my profiling and crime scene training proved useful later on as an investigator! My husband thinks I would have ended up in a medical profession had I not had our kids so young and devoted myself to being a full time mom.

Fiona - 
What was the most surprising thing that came with your shift from field work to lab work? And that begs the question - how much time had you spent (by percentage field v lab in your capacity as CSI?)

Karen Sue - 
Unlike TV, the crime lab has a different crew than the forensic technicians who collect the evidence. 


Even though trained as a CSI, my job at the Coroner's was specific to evidence related to the death itself. If I had a homicide victim of a gunshot for instance, I needed to take note of the caliber of any casings but I did not collect them. The CSI/Forensic Tech did that. Even if there were hairs or other evidence ON the body, I assisted in collection but signed them to the CSI who then delivered and signed them over the Lab tech for analysis.

That is a pet peeve of mine. Unfortunately TV makes it look like any one of us can do all parts of the job, but it does not work that way. There are actually so many different "jobs" involved in the process. Everyone has their part. Even with as many different people involved, it still takes a long time to process evidence. If one of us were doing all the different parts it would take forever. I realize TV has to modify their show to get things done in a timely fashion, but sadly many families think we can also get things done that quickly and we can't.

As for field work verses what I will call "desk time", I would say I spent more time at my desk researching disease, reading through stacks of medical records, speaking with doctors about their patients (my decedent), tracking down long lost family members of transients, researching medications and their side effects, talking with other agency investigators and district attorney investigators as well as writing up my reports.

Not all cases warrant a field response. That is one of the many things I plan to clarify in the website I am working on - how it is decided what happens next with a case.

Fiona -

Let's take a moment and talk about the amazing resource you are developing for us writers.

Karen Sue - 
It will have detailed posts of what I do and why! 


I am almost ready to have my new and improved website up as a source of forensic information for writers as well as interested public. 

There will be photos and details of lividity, stippling, decomposition and decubitus ulcers, as well as entomology information complete with photos of my projects. I will also eventually expand into PTSD in law enforcement, what it is like to be a cops spouse, and provide downloadable forms for emergency information for children and the elderly, especially those that live alone.

The website name is “dyingtowrite.com” 


Fiona - 
Here are some photos that Karen Sue took of a staged crime scene - (that's an actor not a real victim).You can find the link just look under "blogs I follow" on my right toward the bottom my sidebar.














Fiona - 
Was it ever an issue in court that you were a death investigator but not a physician?

Karen Sue - 
It has not been so far - for me anyway. I am very careful about how I write my reports. I make it clear that my observations at the scene are external and sometimes presumed until autopsy. In the first couple of years as a tech, I worked many autopsies. I knew from that experience that the Forensic Pathologist would do the dissection of the organs and make the final cause of death report. My job as an investigator was to determine MANNER and the pathologist determined CAUSE OF DEATH. They are 2 separate things but go hand in hand for the death certificate.

Fiona - 
Readers - for more about autopsies, medical examiners and dead bodies go to the DEATH DO US PART tab in the archives above.


Karen - I know that you've left the field now, but did you like doing your job?

Karen Sue -
When people asked me that, I have always replied that I love my job. I worked hard to get the job. People assume I mean I love the gore and such; however, what I LOVE is helping people at the worst time of their life. I have been there myself. My own father committed suicide by gunshot, and I was the one who found him. I HAVE BEEN THERE, and I know how it feels. 


I am grateful for the strength and opportunity to help others when they are in that position. I feel the family members left in shock DESERVE someone who will answer their questions with compassion.

Fiona - 
And finally, here on ThrillWriting it is a tradition that you share a scar story.


Karen Sue - 
I would say my biggest scars are emotional and come from child cases. I have autopsied children as well as worked field investigations of child related deaths. Every case effected me in some way, but the children left the deepest emotional scars. 

One case that stands out to me was of a young boy. He was playing outside and a neighbor's puppy got loose and ran over to the yard where the boy was playing. His father had just stepped inside to get something. The boy was frightened of the puppy who just wanted to play. The boy began to run and the puppy chased him. They both ran out into the street from between parked vehicles. A truck, being driving by a young man in his early 20's was driving down the street at that very moment and unable to stop in time struck both the boy and the puppy. The driver was not speeding, was NOT under the influence and not distracted. He simply could not stop in time. What really got to me was that no one was doing anything wrong. The puppy just wanted to play. The boy was scared. His father was not negligent and was only inside a minute. The driver was not doing anything wrong. And yet here are multiple families who have no other connection but this horrible tragedy and it was nobody’s fault. There was no one to get justifiably angry at. Even the owners of the puppy had done their best but puppies are escape artists. The puppy owners happened upon the death scene as they were out looking for their puppy. I had to tell them not only was their puppy dead, but as a result of its escape a young boy had been killed and a young man forever scared by his part in the event. So much pain and yet nobody really did anything wrong. Nothing that happened was due to wrong doing or bad people. I realized with that case it is easier when there is someone to blame, someone to be at fault, and especially when there is someone to prosecute and punish for such a tragedy but there was not.

So many cases stick with me. I usually would carry out the children myself whenever possible and if I close my eyes I can “feel” the weight of their lifeless bodies in my arms. I feel as though there is damage done to my soul from the evil than I have seen and cannot unsee.


Fiona - 
A huge thank you to Karen Sue for helping us to understand more about crime scenes and the humanity behind the professionals who work a crime scene.

As always, a big thank you ThrillWriters and readers for stopping by. Thank you, too, for your support. When you buy my books, you make it possible for me to continue to bring you helpful articles and keep ThrillWriting free and accessible to all.








Sunday, September 14, 2014

Crime Scene Plotting Gems: Info for Writers w/ USA Today Bestseller Jamie Lee Scott


___________________________

________________________

USA Today bestselling author, Jamie Lee Scott joins me today.


Jamie, as you know, I love to learn how to write it right. And, like me, you like to get down and dirty with the learning process. I know that for your novella you went out on a ride along in Thibodaux, Louisiana thanks to our fellow author Police Chief Scott Silverii. And we were in classes together at the Writers' Police Academy, recently.

Before we get started sharing some of the crime scene plotting gems that you picked up, can you tell us about yournovella?
USA Today Bestselling Author, Jamie Lee Scott

Jamie Lee - 
Sure.

Uncertain Beginnings -
When Sergeant Wyatt Burke goes to the house of one of his officers -  after the man doesn't check back in for duty after his dinner break - he finds him face down on the floor at the foot of his stairs inside his house. What first looks like an unfortunate accident, soon becomes a murder investigation, and takes Sergeant Burke into darker shade of blue.

Though my novella, Uncertain Beginnings, is the first in my "uniformed" police procedural series, I've written six private detective agency novels prior to this series, and I've used the information I've learned from law enforcement and crime scene investigators to write both the P.I. novels and the police procedurals.

Fiona - 
And of course we know that when you said a darker shade of blue, blue refers to cop culture. Would you say your novella is a police procedural?

Jamie Lee - 
Yes, a police procedural. I incorporated what I learned riding with Scott's cops and CSI to catch the killer in my novella. In this case, it's what you can't see that may be the evidence that solves the case.

The seed that started this series was a 12 hour night shift with the Thibodaux police. I watched, followed and listened. It helped to get the details of how cops interacted with the public and how the public interacted with them.

Fiona - 
And today we are going to be sharing gems from your CSI class.

One thing that doesn't show up in many books is that there is a series of hand offs in a criminal death (or an unexpected death).
1) The police have to give the okay that the area is safe before the
     EMT can go help someone.
2) The EMTs go in and help the injured person or declare the
    person deceased and give them a time of death. The official
    time of death is when the EMT makes the declaration and has
    nothing to do with the actual time that the person died.
3) The EMTs hand the scene over to the medical examiner or their
    representative. The ME takes pictures and conducts specific tests
    on the body that will help them to make a determination about
    whether an autopsy is required.
4) The ME hands the scene over to the detective - but the body is in
    the custody of the ME

But that's not always true.

Jamie Lee -
In my CSI class at WPA, I learned that not all states have an ME who comes to the crime scene.

The CSI unit works in tandem with the detectives to be sure the scene is processed properly and that the evidence isn't contaminated.

Many CSI investigators aren't police, they are hired companies. The CSI is a trained layperson. In this case a layperson means that they have not taken a police officer's oath.

When the detective determines there's been a crime, they call in the CSI unit, who then comes in with their gear, completely suited up. They expect anyone on the scene to be suited too. This includes booties, gloves, hair nets, white suits (Tyvek).

Fiona - 
When they enter the crime scene can you go through the CSI unit's priorities?

Jamie - 
The scene is first photographed, long distance, to get an overall picture of the scene, then middle distance, gives objects relationship to one another, then close ups.

English: A crime scene. .
 (Photo credit: Wikipedia)
Nothing is touched until ALL photographs are taken, and CSI is satisfied.

After the initial photos, and possibly video is taken:
* Numbered tents are placed
   for possible evidence
   pieces. 
* Items are again
   photographed. At this
   time the evidence may be
   collected. There are
   different types of 
   collection containers. 
The containers are usually paper, 
   but may be hard plastic, in the
   case of a container for a knife.

Patti Phillips, photographer "Grab the CSI Kit"

Fiona - 
What are some details that you found surprising about the packaging?

                                                               Patti Phillips, photographer "Grab the CSI Kit"

Jamie Lee - 
All wet evidence is dried before packaging, and rarely is plastic
   bag used unless there is zero % chance of mold.
* DNA is packaged in paper.
* When the evidence is sealed, it is taped. 
* The information is written across the tape, so that if there is
   tampering, it will be evident. 
* All evidence bags have handwritten Incident Report #, 
   Date sealed, Time, Initialed, #items, and new opening each
   time the package is opened.
* The information is written on the package every time it's opened,
   and the new info is again written across the tape.
*  Only CSI can touch the contents. Lawyers can look at it, but not
   touch, but then no one wants to touch if they don't have to.
* Each time the evidence bag is opened, it must be opened from a
   different side, so the original seals are never disturbed. 
* Once all of the openings are breached, that package will be put in
    a new container, to start over with the original seal.This helps
    with chain of custody.
All evidence is kept indefinitely until released by the courts.
* There are warehouses of evidence from cases that have been
   cleared by the courts, but the statute of limitations hasn't cleared,
   so the evidence is kept.

Fiona - 
Tell us about any evidence collection that was new to you - surprising. 

Jamie Lee - 
When hands are covered for evidence, they are covered with paper bags, to avoid sweating, as that will ruin any evidence.

Fiona - 
On a dead person or on the way to the hospital?

Jamie Lee - 
Any person who was at the scene and may be a witness or a suspect.

Fiona - 
Alive then - who knew!

Jamie Lee - 
We can talk about "swabbing the log"

Fiona - 
Yes, let's do that. what is it?

Jamie Lee - 
When looking for DNA evidence, you need skin.

English: Overflowing toilet
English: Overflowing toilet (Photo credit: Wikipedia)
If you have nothing, you can wait for your suspect to take a poop. Then you "swab the log" because there will likely be some skin shed in the process of eliminating the fecal matter.

The matter itself is worthless, but the skin cells that may have been deposited at the time of defecation can give detectives the DNA they need.

Fiona - 
Argh. So how do you stop them from flushing? And how do you swab a log?  - So awesomely gross!

Jamie - 
I'm not sure how they get the fecal matter in the first place. But if they aren't letting the suspect out of their sight, they may have them go in a facility that they've clogged, or somehow if there are "skid marks" that may hold some matter. 

Swabbing the log would consist of the same protocol as swabbing the inside of a cheek. Only I'd think they'd try very hard to swab the entire surface, as to not miss a chance at getting skin cells.

Fiona - 
And this is why I write about CSI but don't actually do CSI.
Other gems?

Jamie Lee - 
Interesting: GSR, gun shot residue will show on anyone in the room when the gun was fired.

GSR is also extremely fragile and must be processed within four hours.

The most important thing is that ANYTHING can be evidence.

Fiona - 
Give me a "for instance".

Jamie Lee - 
A person who put in a job application on Monday may come back and rob the place on Tuesday. Now you have the robber's address.



My biggest surprise was learning that they use Mylar and a form of electricity to pick up prints.

Fiona -
Wait - how do you do that with a stun gun?
Jamie Lee - 
* They place the Mylar over the fingerprint, then make the
   electrical charge with a stun gun, which lifts the print into
   the Mylar,
* The static charge on the dust particles cause the Mylar film to be
   sucked into the surface.
* T
hen the air bubbles are rolled out with a fingerprint roller, and
   the print can be examined with a light. A flashlight will work. It's
   just to make sure you got the print before you affix it to a more
   secure surface. And it absolutely can't be in contact with plastic
   because it will remove the static charge.

Fiona - 
Affixed with superglue?

Jamie - 
It is photographed immediately.



That photo is an electronically-lifted print

I know your readers enjoy video quick studies. Here's one I found on Electrostatic Footprint Lifting with Dr. Shaler. In this film he:
* Shows the film
* Shows the electrostatic lifter
* Step by step procedure including using a brayer to get rid of air
   bubbles
* Electrostatic print can be lifted from paper, carpet, almost any
   surface. But the print can not be made with water. It must be
   made with dust.


Fiona - 
Very fun stuff! Thanks so much Jamie Lee for stopping by ThrillWriting to share. Before you go, we always like to hear your favorite scar story.

Jamie Lee - 
I have a scar on my face, under my nose on the left side, and everyone always thinks it's a pencil mark, if they see it at all. I was in a car accident when I was 5 years old. 

My dad was driving our Riviera on a raining night, we were coming home from my grandfather's art gallery on Cannery Row in Monterey, CA, and he tried to pass a motor home. The motor home sped up, and my dad lost control of the car and hit a tree head on, I went through the windshield. Yes, I had a seat belt on, but in those days it was only a lap belt. 

The cut was on the left, and my body was black and blue on my right. I have no recall of the accident, or several days after, nor do I have any memory of my life before the accident. I'm probably one of the few kids who has no memory of kindergarten. 

Fiona -
Thank you Jamie 


Thank you so much for stopping by. And thank you for your support. When you buy my books, you make it possible for me to continue to bring you helpful articles and keep ThrillWriting free and accessible to all.





Wednesday, March 19, 2014

Forensic Trace Evidence: Hair and Fur - Info for Writers




CRIME SCENE DO NOT CROSS / @CSI?cafe
 (Photo credit: Wikipedia
So your investigator arrived on the scene.
(Crime Scene 101 for writers article)

They've photographed and collected all of the macro-evidence. 

Now they need the trace evidence (that which isn't easily seen with the naked eye) collected and processed. This trace evidence might include hair. 
* Hair is one of the most collected forms of trace evidence.
* Hair is particularly useful because it is stable over time.
* Because hair is produced around blood vessels it is a long term
   record of toxins
   ` Illicit drugs such as THC in marijuana
   ` Poisonings such as arsonic
   ` Heavy metal exposure such as lead.
   ` Medications
* Hair grows at a fairly predictable rate of about .5 inches per
   month. So scientists can even calculate when the exposure to
   the toxin began - depending on the length of the hair.


Investigators will use three basic means of collecting hair and other trace evidence.

1. Hunt and peck
2. Tape
3. Vacuum
Video Quick Study (9:50) Prt 1 
Video Quick Study (1:54) Prt 2 Teacher explaining collection
                     methods of finding trace evidence including hair. 



Humans have various hair all over their bodies including body hair, eyelashes, and eyebrows. But only head hair and pubic hair have forensic use.


So let's say we have a rape victim. They find hair on her clothes. 
1. They will have to collect hair from the victim - this is a known or
    K sample
2. The laboratory will compare the victim K sample to the 
    Q sample - the sample in question.
    a. First, they will figure out if the Q sample is a human hair.
    b. Second, They will determine if the K and Q samples have
        the same general characteristics.

Let's say that the victim K sample excludes the Q sample that is they could not come from the same person. But our investigators have their eye on a bad-guy. They ask him for hair samples. He can 
a. Agree and submit to testing
b. Refuse - if he refuses then the courts can order him to submit.

The suspect K sample is collected.
1. It is suggested by the FBI that 100 full, intact strands, including
    the follicle are harvested from the suspects head from various
    regions as even hair from an individual person can differ
    from region to region on their heads.
2. It is suggested that at least 20 intact strands of pubic hair are
    obtained.

*If the laboratory says that the suspect K sample and the Q sample
  do not share similar qualities, this excludes the suspect. 
*If the lab says that there are similarities in the K and Q samples,
  this DOES NOT mean that you found your villain. 
* Hair is class evidence - it can be used to exclude but not to prove
   someone is culpable.
* If there are similarities, the sample is sent for DNA testing.
  (DNA 101)
* By doing lab analysis first, it saves a great deal of time and money
   over going right to DNA analysis

Let's do a little biology 101 - I know you're excited!

hair follicle
(Photo credit: Wikipedia)

* The root of the hair is
   anchored into the dermis of
   the skin
* Follicles are surrounded by
   epidermal cells
* Blood vessels at the roots
   deliver nutrients






Looking at the hair itself

* Hair is mostly made
   from keratin
Haarstrukturen im Vergleich
 (Photo credit: Wikipedia)
* The outside of the hair is 
   called the cuticle
* In humans, the cuticle
   gives very little information. 
* Mammals have various
   patterns in their cuticles and
   the labs can compare the
   various patterns to tell
   that's a bat, or a rabbit, or a
   werewolf. 

* Inside of the cuticle is the cortex.
* The cortex is the thickest layer of the hair strand.
* This is where pigment from the melanin can be found, giving hair
    its color.
   ` Hair colorant can coat the surface or penetrate to the cortex.
   `In bleached hair pigmentation is lost from the cortex
   `Only the hair that is treated will show a change in color, so at the
     root the true color will be visible. There will be a line of 
     demarcation between the two

* When people change the color of their hair, or their hair changes
    naturally as the subject ages, this can create issues in finding 
    similarities in the K and Q samples. 
* PLOT TWIST!
   A fingerprint cannot be altered, but your villain can thwart an
   investigator by dying their hair, committing a crime,
   and then dying their hair a different color. So even if the police
   take K samples from their hairbrush they will not show as similar
   in the lab. And when they take them from hair that's been altered
   it too will not show as the same.



Photomicrograph of Pubic Hair Medulla
Pubic Hair Medulla (Photo credit: Wikipedia)
The Medulla
* The medulla is at the core of the hair sample
* It is the hollow region at the center.
* A data bases of medulla patterns have been developed to
   identify various animals and differentiate human from other
   animal hair.
* Finding animal hair can be very helpful. It can link transferred
   hair from a suspect at a crime scene. For example, Blade Slayer
   goes in and attacks your heroine. Trace evidence hair is found.
   It's a black rabbit, and Blade Slayer happens to have a black
   rabbit named Cuddles. It's circumstantial, but it can be helpful.
* Animal hair forensics can also be used in crimes like poaching
   and illegal animal importation (Wildlife Forensics Blog Post)


Three Phases of Hair Growth

Anagen Phase
* 2-7 yrs for scalp hair 
* Growth phase where cells are formed at the root which pushes the
   hair out of the scalp making the hair longer.
* This hair will only fall out if it is yanked out.
* When hair from this phase is
Animation of the structure of a section of DNA...
Animation of the structure of a section of DNA. The bases lie horizontally between the two spiraling strands. (Photo credit: Wikipedia)
   found at the crime scene it has a
   follicle attached. 
* The follicle contains DNA that
   will identify an individual
Catagen Phase
* The hair is in transition
* The hair no longer grows, the
   cuticle pulls away
Telegen Phase
* The final phase where hair falls
   out.
* In the catagen and telegen
   phases the follicle is no longer
   attached to the hair. Nuclear
   DNA cannot be found. The
   investigators will try to test for
   mitochondrial DNA in the hair
   shaft. Mitochondrial DNA is not
   conclusive as everyone in the
   matriarchal line will have the
   same DNA (DNA 101 for Writers)
* Telogen hairs are those typically found at crime scenes.
* Because hair is easily transferred from one place to another, it is
   circumstantial evidence.

What else can an investigator tell from a hair strand?

* Pubic hairs have shaft differences along the length and a
   continuous medulla
* Male facial hair is usually more triangular in shape
* Hair that's been cut or shaved will have a blunt end
* Hair that is allowed to grow naturally such as arm hair will have a
   naturally tapered end
* Head hair - not recently cut- will show a frayed or split end
* Age cannot be discerned.
* Sex cannot be determined.
* Ethnicity - is difficult. The person would have to have a very
   clean background as Caucasian, African, or Asian ancestry.
   And then, there are variables that can point the investigators
   in a direction. It is not conclusive.



So what can an investigator say about a hair sample?

* Is it human, or animal (or vampire)?
* Is it a useful sample, either head or pubic hair?
* Is it head or is it pubic hair?
* Is the Q sample consistent with the K sample?
   `If yes, further investigation - suspect stays in the pool.
   `If no, suspect is removed from possibilities; they look for another
    suspect.
   `If yes AND no that is there are similarities AND differences,
    then no conclusion can be drawn.

Video Quick Study (4:16) Hair testimony at Casey Anthony trial
Video Quick Study (4:27) Britain CSI school


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Monday, March 10, 2014

Forensic Serology: Body Fluid Information for Writers


______________________________________


Soldiers of the United States Army Criminal In...
 (Photo credit: Wikipedia
At the scene of a violent crime, investigators will look for serology samples.
(CSI blog link)

Serology is simply the study of bodily fluids.

These fluids include:
* Blood
* Semen
* Saliva
* Sweat
* Tears
* Vomit
* Vaginal secretions

These fluids can be found either on the skin or transferred to another surface.


While serology tests can EXCLUDE a subject who is thought to be a person of interest, it can not find them culpable.

Serology tests are class studies and cannot tie a body fluid to a specific and unique source.
Only DNA testing can link a specific individual to a crime. (DNA blog link)



Presumptive tests - likelihood of something being what you think it is in the field.

* Sometimes a false positive - but you never want a false negative because then a detective could walk away
   from evidence and make false conclusions about the scene

Is there blood present but not visible to the naked eye?
* Fluorescein - precursor to Luminol goes back to 1900s
   `Is not thwarted by chlorine bleach
Blood Stained Floorboard Treated with Luminol
Blood Stained Floorboard Treated with Luminol (Photo credit: Jack Spades)
   ` Uses UV light to glow
   `Still used in the field today
   `Thicker than Luminol so good for
     vertical surfaces
* Luminol/BlueStar
   `Does not work if chlorine bleach
    was used to clean up the blood
   `Complicates further testing by
    diluting the blood
   `Needs darkness



When you write a scene that includes either of these tests, please remember that the blood is not visible to the naked eye because it was cleaned up. When the blood was cleaned, it was smeared around. The Luminol or Fluorecein will show up in smear streaks NOT blood spatter. NOT hand prints.

Video Quick Study (2:49) Shows luminescence of BlueStar

Is that blood? Testing for a visible stain:
At FBI doing serology tests
* Leucomalachite Green
   Video Quick Study (4:28)
* Kastle-Meyer test - phenolthaline and hydrogen
   peroxide that detects the hemoglobin in blood
   cells.
   `produces a dark pink.
   `blood can come from any animal
   Video Quick Study (1:01)

Video Quick Study (7:41) CSI teacher shows how the three presumptive blood tests are conducted.


Once the presumptive tests show that a substance is blood then the collection is sent to the lab where they undergo confirmatory tests:

1. Is it human blood?

   * The serology labs have stocks of antigens that are found in animals but not humans.
   * Samples of common animals such as: dog, cat, rabbit, deer, chicken etc. antigens  are maintained for
      testing.
   * If the test shows an antigen reacting with an antibody then that determines the species type.

2. Once it is determined that the blood is human then blood test typing is done.
   * Blood Type
Diagram of ABO blood groups and the IgM antibo...
Diagram of ABO blood groups and the IgM antibodies present in each.  (Photo credit: Wikipedia)
    `ABO system
    `Rh Protein (not used in forensic science)
    `Genetically inherited
    `Can be determined not just from
     blood but also from other body secretions.
    ` Blood type is class evidence. It is NOT
      individuating evidence. So it can only be
      used to show that someone COULD NOT
      have done the crime but cannot be used to
      prove that some did - that would require
      DNA




Video Not Quite So Quick Study (14:00) Goes over this thoroughly if it is an important point in you plot and you need a firm grasp on the importance of blood typing.




Semen

Sperm (album)
Sperm (album) (Photo credit: Wikipedia)
* Can be found in a dead woman's body for up
   to two weeks
* In a living sexual assault victim sperm can only
   be found for about five hours after the crime
   occurs
* After 72 hours in a live victim there may be no
   remaining evidence of sperm or semen
* Acid phosphatase is a presumptive field test.
   Acid Phosphate is made in the seminal
   vesicles in males but also in:
   `non-human animals
   `plants and fungi
   `found in vaginal fluids.
* Microscopic search for sperm cells in a
    sample is a confirmatory test
 * Microscopic sperm search is NOT useful if
    the man has had a vasectomy
* PSA (Prostate-specific Antigen) is considered
   confirmatory

Video Quick Study (1:01) Acid Phosphatase Test


Video Quick Study (3:15) Storage and container information for serology samples
Video Quick Study (2:31) Serologist at trial giving testimony - note the packaging of the items

Using various wave length light sources to find bodily fluids at a crime scene
All body fluids fluoresce except for blood which absorbs light
Body fluids must be dry to fluoresce except for urine (which will sometime fluoresce when wet)
Video Quick Study (2:00)


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Thursday, December 12, 2013

Forensic Entomology: Something's Bugging Me About the Murder Scene

__________________________




Description: Calliphora vicina. Blow-flies (al...
. (Photo credit: Wikipedia)
WARNING: The photos and videos contained in this blog may be considered graphic in nature. Please 
consider your tolerance before viewing.



Your character arrives at the crime scene ready to put her full professionalism into play and solve the crime.
Uh oh! They've found a body. Your heroine calls in the coroner  because it's required by law. But very quickly, your heroine realizes from the state of the remains that the body has been decomposing for over 72 hours. So she makes two more calls:
Blow-flies
Blow-flies (Photo credit: Wikipedia)
* the forensic anthropologist to process the remains.
* A forensic entomologist to process the bugs.

- Blog Link to Crime Scene 101
Blog Link Coroner/Death
   Investigator
Blog Link Algor, Livor, and
   Rigor Mortis
Blog Link Forensic
   Anthropologist

* In the first 72 hours there are more precise ways to
   determine time of death than by using insect evidence.
* After 72 hours insect evidence is the most accurate
   and possibly the only way to determine time of death.


A forensic entomologist - deals with any bugs that would show up in the court of law. 

Video Quick Study (2:42) a forensic entomologist talks about his job.


Sometimes, because of access, distance, or budgets, getting a forensic entomologist to the crime scene is not possible. A CSI can gather the evidence.

A Typical Crime Scene Kit
A Typical Crime Scene Kit (Photo credit: Wikipedia)
Video Quick Study (1:36)  Review of a field forensic entomology kit.
* Different species should be kept separate
* Insects collected from different body parts should be kept
   separate.
* Maggot clusters should be documented, photographed, and
   temperatures obtained.
* The specimens should be labelled with:
   - date and time
   - name of the collector
   - stage of insect development at time of the collection
* When the bugs are collected your character will want to have 2
    vials:

- Sample One - contains alcohol (the bugs die) this shows:
   1. what stage of development the bugs were in when they were
       collected
   2. helps the emtomologist to define the approximate time of death
   3. can be used  in court as evidence.

- Sample Two - keeps the specimens alive. Add a dampened paper
   towel and cover with dry paper towel held on with a rubber band.
   This allows the entomologist to incubate the insects in their lab 
   and determine a  more specific time line.
  

Other data that will help a forensic entomologist make sound scientific inferences in the laboratory include:

* Habitat: ex desert, vegetative, meadow, woods
Ruler in use at a mock crime scene
Ruler in use at a mock crime scene (Photo credit: Wikipedia)
* Soil samples
* Weather at the time of collection 
    including: shady? sunny? 
    raining? temperature?
* Vegetation in the area
* Death site including elevation
   and map coordinates
* The state of the remains
* Were the remains buried? How
   deeply?
* What clothes or wrapping
    surround the remains?
* Anything else that the CSI thinks
   might help inform the process.

Photography is VERY helpful

Video LONG Study (15:11) Prt 1, Canadian entomologist discussing crime.
Video LONG Study (6:42) Prt 2


Okay, let's get to the bugs themselves

English: Describing the relationships between ...
English: Describing the relationships between carrion insect trophic specializations and decomposing remains, adapted and simplified from K.G.V. Smith, A Manual of Forensic Entomology, 1986 (Photo credit: Wikipedia)
Some terms: 
* Nacrophagous Species - feed on dead things.
* Omniverous Species - will eat most anything
* Predators - come to eat the necrophagous and omnivorous
   species of insects
* Parasites - are brought in by the other insects
* Adventive species - can be particularly informative. If the
   entomologist finds sub-types of species whose habitats are in a 
   different geographical location, they can determine that the body
   had been moved.
    Video Quick Study (1:49) Entomologist looks at the air filter on       a car to determine if the suspect drove  across the United States 
    to commit a murder.


The first on the scene is the blow fly.


English: Sarcophaga (Liopygia) ruficornis fles...
English: Sarcophaga (Liopygia) ruficornis flesh-fly mating.  (Photo credit: Wikipedia)

* Blow flies can smell death and
   can be there in mere moments.
* They lay their eggs immediately
   in openings. This can
   mean: mouth, eyes, nose, ears, 
   anus and vagina, and
   importantly, wounds. 

Now why is that important? If the remains have decayed past the point of recognition, finding the maggot mounds can help identify where that person might have been injured.

Why might this be bad? - When the eggs hatch and the larvae
starts to eat they are:
* destroying the facial features of the deceased, making
   identification more difficult
* can damage the wound margins making forensic wound study
   difficult.

Quick review of your Biology 101 class - here are the stages of blow fly life:
1. egg is laid - NOTE: flies
    are only active during
    daylight. If the person dies
   at night, the first eggs
   won't be laid until
    morning.

Video Quick Study (2:11) fly laying eggs on deceased bird.

2. maggots come out and start to consume the corpse
3. larvae grows and eats
4. The larvae are full and stop eating. They migrate away from the
    body to pupate (hard cocoon-like stage while their DNA
    rearranges them into a fly). They like to do this in cool
    conditions. They will crawl under rugs, into the clothing
    especially seams, pockets, and cuffs, or if this isn't available -
    earth.
5. Pupae - because they change color can be aged to a matter of
    hours.
6. Emerging as a fly

* This whole cycle takes about 2 weeks depending on:
- Species 
- Weather (warmer temperatures creates more activity)
- Quality of the food
- Oxygen levels
- Day length/season

Video Quick Study (6:52) Close up video of blow fly life cycle.

Video Quick Study - Murder case in Hawaii where the body was wrapped in blankets.
.

* If a body is discovered in the first month postmortem interval, PMI, entomologists can be accurate to
   within a day.
* After first generation of blowflies has developed, the
   entomologist looks at the succession of insects. This is
   used when the corpse is dead for a month or more. The wave of
   insects overlaps.



Insect Arrival Comes in Waves

English: Blow flies (chrysomya megacephala) on...
English: Blow flies  (Photo credit: Wikipedia)

1. Flies - attracted by the
   decomposition odor arrive
    immediately. They like fresh
    bodies because of water
    content.






Oiceoptoma thoracicum (Silphidae)
Oiceoptoma thoracicum (Silphidae) (Photo credit: gbohne)
2. Carrion Beetles - Arrive in a few days
    during putrefaction stage
    body liquids are starting to expel from
    the corpse, lot's of odor
    more and more insect activity. (flies
    and wasps will also be
    there)






Closer view of a carpet beetle
Closer view of a carpet beetle
(Photo credit: Dendroica cerulea)
3. Carpet Beetles - come during the dry stage - skin is hardening
    an becoming leathery, some bone is starting to protrude out of
    decomposition. The carpet beetles come to eat the hair, skin
    and bone. Coffin flies, cockroaches and flies are there as well.

Video Quick Study (8:53) a forensic teacher takes you through the insect stages.
Video Quick Study (7:31) video of an animals decomposition, focusing on insect activity

Interestingly, bugs:
* can carry corpses dna
* can ingest drugs
Video Quick Study (2:45) Student's on site
Video Quick Study (6:38) Student forensic entomologists.

* Bugs can only tell the entomologist how long the body has been
   available to the bugs. So for example, if the body was in a deep
   freezer and then removed  and put in the woods, the timing would
   be based on when the body was available to the bugs.
* In much of Canada and northern United States, cold winter
   months mean entomologists cannot use insects to determine time
   of death.
* In the summer, a body can decompose down to bones in as little
   as two weeks.
* Decomposition in water - standard insects don't apply but other
   organisms do.





CRIME SCENE DO NOT CROSS / @CSI?cafe
CRIME SCENE DO NOT CROSS / @CSI?cafe (Photo credit: Wikipedia)



CASES


Collecting insects at a mock crime scene
 (Photo credit: Wikipedia)
1. Video Quick Study (3:58) Prt 1
   Video Quick Study (3:32) Prt 2

2. Video Quick Study (1:42) Entomologist testifying
     in Casey Anthony Trial

3. Video Quick Study (1:49) Entomologist looks at
    the air filter on a car to determine if the suspect
    drove across the United States to commit a
    murder.




See how this article influenced my plot lines in my novella MINE and my novel CHAOS IS COME AGAIN.





Thank you so much for stopping by. And thank you for your support. When you buy my books, you make it possible for me to continue to bring you helpful articles and keep ThrillWriting free and accessible to all.