Unusual work accidents: Forens...

Unusual work accidents: Forensic challenges in evidence collection | Terri Armenta

Expert Profile:

Terri Armenta is a forensic educator for over 15 years and has used her experience and knowledge in biology and chemistry, along with her specialized training in forensic science, to carve a unique niche in teaching and developing courses and curriculum in the field of Forensic Science and Criminal Justice topics. She has completed her formal education by obtaining an MS in Forensic Science and has supplemented this education with training from local police agencies, criminal justice classes, specialized training programs, professional law, and forensics-related conferences. In addition, she holds professional memberships in educational, legal, and forensic organizations. During her teaching career, she heard over and over again: You have the degree but not the experience. So she decided this was her passion (to teach students) and her mission (to help them get started in their forensic career). She combined both and created, Forensic Training Unlimited, which specializes in training students with the skills needed to apply for forensic positions. Forensic Training Unlimited, LLC, offers forensic courses, workshops, seminars, online courses, and sponsors the Forensic Science Academy, a hands-on academy offering over 200 training hours. This Academy has been in operation since the late 1990s and has trained many individuals who now hold professional positions in the forensic, legal, and law enforcement field. 


The present lecture emphasizes the Forensic challenges that are encountered in various cases of unusual work accidents. The speaker has well-introduced learners to the subject matter incorporating the review of the Los Angeles county medical examiner, coroner, the whole background, etc. Special focus is given on the crime scene photographs and discussion over it. Indeed this session gives a crisp knowledge of the forensic challenges in evidence collection adequately covering all its related aspects. Terry has opened her talk by shortly introducing her carrier and achievement in the field of forensic science.


By introducing her talk she has explained about the crime scene as a place where a crime occurs, whether natural, accidental, suicidal, or homicidal in nature. Further, she continues by saying that every crime scene is unique, so the challenges faced are also unique for every crime scene. Certain steps should be kept in mind while carrying out an investigation. And terry called them as ABCs of Investigation. 

ABCs of investigation

Assume nothing
Believe no one
Check everything 

She further adds that what may appear to be true at a crime scene at the first look may not always be true. Preconceived notions and assumptions should not be made as they might lead to false results. She showed two examples from the case images, the left one looks like a vehicle passing over the body and the right one is looking like a suicide case but our speaker strongly suggests to not get dependent on the facts that are visual and never let your presumptions to guide you while investigation because mostly the crime scenes are all about what is not visually depicting and here comes the role of the forensic investigator to thoroughly observe the whole scenario, check for every detail twice and collect and analyst evidence accurately and precisely.

Review of Los Angeles County Medical Examiner-Coroner 

The investigating team doesn’t just contain investigators, but also a whole lot of other people. Investigators don’t work alone while investigating a crime scene. A whole investigative team plays the backstage role in the culmination of an investigation. The team could involve detectives, First responders, Criminalistics, Witnesses, crime scene investigators, law investigators, medical professionals, or anyone who brings information to the particular case because not one person can do it all. The team could vary depending upon the nature of the crime scene.
As per a Los Angeles medical examiner's concern, she told that the coroner at Los Angeles is the busiest person who covers over 5000 square miles for investigation per day and conducts over 7500 autopsies per year. Mostly in the medical examiner offices, they do not have a budget for having their staff for specific tasks regarding a case such as photography, evidence collection, or autopsy investigation. but in Los Angeles, there has been a team of corner personal which includes investigators, forensic attendants, criminalistics, photographers, evidence custodians, and autopsy technicians and other special and expert officials as per the requirement of the case. Each coroner’s office deals with the cases on natural causes, buried bodies as well as an unnatural crime scene. 

Case Study 

She has discussed a case of workplace death accidents of an employee of a wood chipper company. Before getting into the case details she has explained about the working and instrumentation of the wood chipper which has been the main culprit in this case. The main function of the wood chipper is to take the trimmed branches from the feed tray and pulverized them and shrugged out into another collection device. In this case, the wood chipper was a mobile commercial machine mounted on a frame on a single axle commonly used for tree trimming. The feed tray of this wood chipper was 55 inches with the Chute of 36 inches and a feed wheel that rotates in the direction of the operator. It also has steel teeth engage with the material and the debris is expelled through another chute (a big truck, was the collection device in this particular case). 

Case Background

Two employees of a wood chipper company are employed to clear a locality of the tree debris and branches. One of them is sitting high on top of a tree trimming the branches and the other is near the machine feeding it with the trimmed branches. 
All of a sudden the worker near the machine disappears and blood and tissue are seen at the mouth of the wood chipper. In the inception stages, it was prematurely assumed that the worker got sucked into the wood chipper without looking at any evidence. 
The debris is collected from the wood chipper but it poses a challenge.

Challenges encountered

Other teams of experts to be called upon, to take apart the whole wood chipper.
Uncertainty and unawareness as to the collection of such kind of evidence as all the tissue are outstretched and pulverized. 
Whether evidence obtained will be recognizable or not.
Getting larger pieces of evidence to a processing area.

Strange remains!

Upon detailed investigation and sifting through the tissue samples, shreds of clothing were obtained. One such shred contained a unique account number belonging to the employee under question. This proved to be an important piece of information. Also, boots with intact feet were obtained from the drum of the wood chipper, along with underwear. 
These were further verified by the wife of the employee.
The worker is then declared dead upon identification through the unique account number, boots, and underwear found inside the wood chipper. 

The wife of the deceased filed a suit on the wood chipper manufacturing company. The company claimed that the worker must have fed wood from the front instead of the sides of the wood chipper. However, the wife’s team claimed that due to the lack of any safety measures and a fail-safe system, the unfortunate incident occurred. 
Judgment was passed in favor of the wife, that failure to install a safety system in a wood chipper would have eventually caused such an accident. 


No matter how big or small a role a person plays in the investigation, it should always be thorough. Whether, photography, evidence collection, sketching, report writing, etc. all should be carried out thoroughly without leaving a stone unturned. A thorough investigation will be of help in the court of law.
Personal Note

The session was so full of information and a detailed description of a very interesting case where even though the story can be assumed but the assumption has not been overlaid to the detailed investigation which is very important to reach out to a certain conclusion. For a more detailed view of this case, I would recommend visiting the playlist for the International Lecture Series of SIFS India from 2020 at our YouTube Channel, forensic365. 

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