Sirchie

FW: “Can’t get rid of the blood?”

 

 

Continuing the series of articles about Evidence Collection Training Classes held at SIRCHIE.

Click here for Part 1 – “Have you been fingerprinted?”

Click here for Part 2 – “Where are the Evidence Collection kits made?”

 

Part 3 – “Can’t get rid of the blood?”

 

The morning of Day #3 of Evidence Collection Training classes at the Sirchie Fingerprint Laboratories in Youngsville, NC was spent on the tour of the company’s manufacturing facility. We watched as fiberglass fingerprint brushes were made from start to finish, saw riot helmets being assembled, heard the printing presses rhythmically slap logos and directions onto stacks of waiting cardboard, saw employees counting and rechecking boxes of supplies and chemicals. We witnessed a smoothly running facility. That’s what it takes to insure that the products the law enforcement community uses to catch and prosecute the criminals work. Every time, without fail.

 

After the tour, Robert Skiff (Training Manager/Technical Training Specialist at Sirchie) told us about a new method of fingerprint enhancement developed in Scotland. A bullet can be placed in the middle of an apparatus that shoots electric current into the cartridge and reveals the moisture from a print. This method was demonstrated on an episode of Rizzoli & Isles. Kudos to the show’s writers for including this fascinating technology!

 

Another interesting piece of equipment is the ElectroStatic Dust Print Lifter. Impressions left at a crime scene in the dust on the floor, or on dusty doors or walls, can now be lifted and preserved. A shot of electricity is applied to foil cellophane and any dust below/behind the lifting mat will stick to it. If there is a palm print or fingerprint, it will show up as a mirror image of the original. Rough floors or brick surfaces where a suspect may have jumped, can now be processed using this lifting method.

 

Our afternoon training segment dealt with blood and other bodily fluids.

 

Bloody crime scenes are horrific, but law enforcement officers have to put their feelings aside in order to process and maintain the chain of evidence. Everything they do is aimed at furthering a case to convict, so the scene needs to be secured in order to keep people or animals from contaminating the evidence. If blood is visible at the scene, photographs are taken before the collection process disturbs anything. The photos assist in showing the overall patterns and placement of the drops and splatters. Investigators can determine the approximate place in the room where the victim was first struck, whether the victim was dragged or bludgeoned or shot, if there were one or several victims involved, the velocity of the strike, whether there are arterial spurts, etc.

 

Examples of blood spatter patterns

 

 

 

In order to accurately demonstrate and then analyze the scope and nature of the spatters, the area covered with visible blood is measured and scaled (paper rulers are applied next to the surface being photographed).

 

Blood spatter tagging and scaling

Then it is tagged with information that will help the investigators figure out the sequence of events during the commission of the crime.

Blood Spatter Trail

Specific characteristics of the droplets – whether there is a tail or shaped like an ellipse or a circle, whether small or large circular drops – all reveal information to the investigators and examiners. TV and movie watchers often hear the phrase ‘blunt force trauma’ as a cause of death. This most likely means that the victim has been struck with a baseball bat or a bottle, or a golf club (my fave fictional instrument of death) with medium velocity, so the droplets will be medium sized. (See the drop several inches in front of Mr. Skiff’s finger)

 

A high velocity hit (from a bullet) will have smaller droplets because the blood is broken into smaller pieces as it leaves the body and is sprayed onto the walls or floors.

 

Weapons that are close to the scene or involved in the crime, may get blood on them. They need to be processed for blood as well as prints.

 

Blocking out area of floor of interest to investigator

 

After the visual scans of the room for the visible blood, and the initial photography has been completed, then the areas of possible bloodstains can be swabbed, the samples bagged and identified (as to placement in the room). Presumptive tests can be conducted at the scene, using the Field Kits that contain chemicals commonly used for this purpose. Presumptive tests can help eliminate stains that are not blood, but the stains cannot positively be identified as blood until taken to the lab for confirmation – a detail that TV crime shows frequently fudge.

 

An added level of security for preserving a sample is to make transfers from the original or take chips of the original, but not test the original. That insures that additional tests can be conducted at a later time on the original or pieces of it.

 

 

Unknown Stain

 

 Three transfers were made from an Unknown Stain and then tested with various chemicals.

 

Latent Bloodstain Reagent Products

 

 

 

Unknown stain luminesces

 

 The third transfer was sprayed with a bloodstain reagent, and then the lights were turned off. The Unknown Stain luminesced, therefore indicating the presence of heme, a portion of hemoglobin.

 

If there is no visible blood in the room, but a crime has been reported as having been committed at that site, it is common practice for investigators to work in teams to process the room. The room is darkened, one investigator sprays the walls with a blood search product, while the other marks (tags) the spots that luminesce. The lights are turned on and then the room is photographed, then processed/tested. The method of spraying and tagging is repeated for floors as well.

 

It’s worthwhile to note that blood cannot be destroyed with paint. No matter how many coats, no matter what color paint is covering the evidence of the deed, the tests will always reveal that blood has been spattered beneath it. It gets into every crack and crevice. And it just can’t be washed away. Remember the ‘trace evidence rule’? A crook always leaves something behind.

 

For all you crime show TV junkies out there (I’m one of them): that red blood you see on the bed or wall or floor (hours after a murder has been committed on the show) is strictly for visceral effect. Human blood turns brown or almost black as it dries.

 

 

 

Sexual Assault Collection Kit Record

 

Unfortunately, reports of sexual assault crimes are on the rise. But, ‘He said, she said,’ cases are difficult to prosecute because there are rarely any witnesses to the crimes. Samples taken from the victims need to be pristine and chain of custody must be clearly established. Clothing and bodily fluids need to be collected from the victim as soon as possible after the crime in order to have a chance of catching and prosecuting the perpetrator. A good practice for evidence collection from victims who arrive at the hospital is to have them disrobe while standing in the middle of a sheet. Then the sheet corners can be pulled together, keeping as much evidence as possible intact. Rape victims may not wish to be touched, but swabbing their bodies for fluids, then bagging and testing whatever is collected, may be the only way to tie a suspect to the rape.

 

 

Seminal Fluid Test

A presumptive test can provide important information to include (or exclude) a possible suspect from consideration. There will be an instant (up to 3 seconds) reaction if the unknown substance at the scene or on the victim’s body contains seminal fluid. If the results take longer than that to appear, it must be reported that a false-positive has been found. This might happen if there is not enough of a sample or if the transfer made from the original sample was not good enough.

 

Rape and homicide evidence is kept for years. Bagged, tagged, stored. Photographed and entered in databases as well. If the suspects aren’t caught right away, then the evidence is still there, waiting in storage, to be matched to other evidence that pops up in later crimes.

 

 

*Photos taken by Patti Phillips at SIRCHIE Education Training Center in Youngsville, NC.

 

 

KN, p. 76 “Save the duct tape and glue the dashboard!”

 

Criminals that tie their victims up during the commission of a crime frequently use duct tape for the job. That duct tape is almost always full of prints that get embedded into the tape. It’s practically impossible to manipulate and tear the tape while wearing gloves (I tried this once and the gloves got so stuck to the tape that I threw the resulting mess away), so the crook leaves prints while unrolling and tearing the tape. Even if he has wiped the smooth surface of the tape clean to cover his identity, the sticky side can’t be wiped without taking away the sticky. Balls of tape tossed aside by a suspect have been processed successfully for prints, but first the tape had to be released from itself.

 

Separating folded duct tape from itself

What to do? Drop lots of a 2% chloroform tape release agent on the area where the two pieces of tape meet. Two people need to work together on this – one person places the drops continuously while the other person pulls the tape apart. The ends of the tape should then be folded over (about ¼”) and the tape flattened for 24 hours before doing anything else to it.

 

Adhesive-side developer

 After 24 hours, adhesive-side developer should be applied to the sticky side of the duct tape, allowed to sit for a few minutes, then rinsed off. The prints are clearly visible, can be photographed, covered with clear tape to protect them, viewed under an Optical Comparator, entered into the system, and sent off to AFIS.

 

Duct tape prints

 

 

Dashboard prints:

Up until recently, we could not collect decent prints from the dashboard of a getaway car in a reasonable length of time. Most car and truck dashboards have a slightly bumpy surface, more or less because it’s a selling point to non-criminal types – supposedly the pebbled surfaces mean no more pesky fingerprints to clean off if you’re a mom transporting kids after school. Sheila says the juice spills just get buried in the grooves.

 

But, it’s a potential fingerprint heaven for the CSIs who need to process the abandoned bank heist car. Think about it. If you press your hand onto a dashboard, your skin (with all the loops and whorls and arches and oils) is also pressing into the crevices of the pebbled surface. The problem is that a straight gel lift or hinge lifter will not pick up the prints effectively or may only pick up the top of the print.

 

Dashboard surface

 

 But, the investigator sees the possible print and doesn’t want to lose the opportunity to catch the crook. The answer in the past was to dust the likely area with magnetic fingerprint powder, then apply a Blue Glue gel and wait for the gel to cure before lifting it off the dash – about five hours. FIVE hours? The crook is getting away! No time to wait!

 

These days, the preferred lifting product (after applying the magnetic powder to enhance the print) is a transparent liquid silicone (PVS200 – polyvinyl siloxane), applied with an extruder gun. It flows down into the crevices, dries in six minutes, and gets into every bit of the print. After the polyvinyl dries, it can be lifted, and then placed on a backing card to preserve the print. At that point, it can be placed under an Optical Comparator, photographed, and sent off to AFIS for an ID/comparison.

 

This epoxy is not good for every surface (it rips paper, etc) but is very good for pitted, bumpy surfaces like alligator skin and dashboards. Gotcha!

Dashboard Lift

 

 

Planning to become a crime scene investigator? Then remember to collect the balls of duct tape tossed on the floor or in the garbage cans at the crime scene. Almost definitely, a great source for prints. And don’t forget your extruder gun!

 

*Photos taken by Patti Phillips at the Sirchie Education and Training facility in Youngsville, NC.

 

For more information about Sirchie and its products for the law enforcement community, please visit www.Sirchie.com.

 

 

 

 

KN, p. 189 “Fifth Anniversary Thank You from the Kerrians”

 

Kerriansnotebook_FINAL copy

It’s with great pleasure that we thank you, the readers, for hanging out with us for five years.

 

We’ve taken some really amazing trips to American Civil War battlefields, endured fog and pouring rain on both American and international golf courses, been trapped in elevators, survived bomb scares, witnessed bloody crime scenes, and lived to tell the tales.

 

Some intriguing people have agreed to do interviews about their jobs and in the process, have opened the eyes of our readers far and wide about the rigors of law enforcement in its many forms.

 

Police Academies, Fire Fighter Academies, Emergency Medical Training Schools, Firearms Training sites, Criminal Investigation Facilities –  have all generously allowed us to take photos and chat with the instructors at length. Fascinating stuff.

 

We’ve met with Visiting Detectives – an assortment that included a psychic detective, a vegetarian detective, and a time-traveling detective from the 1800s. Sheila chimed in while they worked on puzzling cases with me. The Vegetarian Detective brought brownies. Yum.

 

Kerrian’s Notebook, Volume 1, which included stories from 2011 and 2012 no longer available on the website, was published in response to the readership that wanted the (over 50) stories from the first year collected into one ebook. Don’t have your copy yet? Click on the link and find it at Amazon: http://www.amazon.com/dp/B00HI6YBDG

 

You’ve made the journey fun. And then some.  🙂

During the years, we kept track of which posts were the most popular, which ones you kept visiting over and over again. For research? For another laugh? To prove a point? For some of you, all three. Here is the result.

 

Click on the links and take a look at your Top 10 Favorite Kerrian’s Notebook posts in reverse order thru 2016:

 

  1. Who are the Texas Rangers?” (p.144)

 

  1. Are all handcuffs yellow?” (p.68)

 

  1. What does a Texas Ranger do?” (p.145)

 

  1. How big is that jail cell?” (p.51)

 

  1. Kerrian’s Favorite Chocolate Cheesecake.” (p.45)

 

  1. 100 Ways to Die an Unnatural Death.” (p.100)

 

  1. What does a firefighter wear?” (p.119)

 

  1. I Like Pie.” (p.67)

 

  1. How many bodies at the scene?” (p.87)

 

And the most popular post?


  1. How to become a Texas Ranger.” (p.146)

 

Thank you, one and all!  🙂
Next time you’re in town, give us a call. We’re always happy to chat about the latest trip or the trickiest case. If you’re lucky, you might even meet one of the Visiting Detectives. There’s always a pot of coffee on and a piece of pie just begging to be eaten.

 

*Fingerprint photo taken by Patti Phillips at SIRCHIE, in Youngsville, North Carolina.

 

 

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