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Researchers from the UK-based Teeside University, have used 3D printing and scanning techniques to advance a key aspect of forensic investigation: Physical Fit Analysis (PFA). Utilizing and comparing two different 3D imaging methods, the research team were able to recreate human bone fragments for use within the PFA process. Not only could this prevent unnecessary damage from occurring to genuine evidence during a Crime Scene Investigation (CSI), but it may also expand on the forensic applications of 3D printing.

Fused Filament Fabrication (FFF) 3D printing proved to be an accurate and useful method for creating physical replicas of the bone fragments, to perform physical fit analysis (PFA) and bone fragment reconstruction. We therefore recommend CT imaging paired with FFF 3D printing, as an excellent option for non-destructive physical fit confirmation, when working with small fragments and burned bone, said the research team.

Physical fit analysis in Crime Scene Investigation

CSI often requires investigators to examine a range of items as evidence, including human remains, some of which may be damaged or fragmented as a result of the trauma suffered during the event. These remains routinely go through PFA to determine whether they fit together. If this process leads to a positive physical fit, it could place suspects at the scene of a crime, or facilitate object reconstruction that potentially solves the case. Nonetheless, PFA involves a great deal of matching and manual handling, which can lead to the fragments becoming damaged during the process.

Moreover, there are instances where PFA can be extremely challenging, such as when fragments may pose a biological hazard, be extremely small, or the bone itself may be too fragile to move. Considering that the reconstruction process usually involves gluing the parts back together, this can cause problems, and prevent investigators from fully understanding the nature of the trauma. This makes certain-shaped bones difficult to document or present, particularly with those fragments that are three dimensional and complex in nature, or embedded in an external material. As a result, two-dimensional representations of such physical fit results are not always sufficient for presentation in courts or interpretation by experts.

While 3D scanning and modelling have been used in a range of forensic anthropology applications, the handling and reconstructing of bone fragments remains an issue. For instance, 3D modelling is currently used in dismemberment, weapon matching, craniometrics and facial reconstruction cases. Volume scanning has allowed for high resolution images to be obtained, on the nanometre scale in some instances, but they tend to be expensive, time consuming and require specialist expertise and software to operate. Surface scanning methods, on the other hand, tend to be cheaper, and more user-friendly, and are often used for postmortem quantitative injury analysis, landmarking, and the analysis of soft tissue injuries.

Additive manufacturing meanwhile, has proved accurate enough to produce dental models for aiding in maxillofacial surgery. Studies have also demonstrated the applicability of 3D printing for the visualisation and analysis of forensic evidence, and the researchers set about combining the technologies to create 3D printed skull fracture replicas. These 3D models offer the potential for PFA to take place without having to excessively handle the original evidential fragments, while minimising any damage or contamination risks. In addition, such models offer 360 degree visualisation in an engaging and understandable format, that could be used to improve jury comprehension during trials.

3D printing skull fragment replicas

The researchers compared Micro Computed Tomography (CT), a volume scanning technique, with structured light scanning (SLS) a surface scanning technique, to assess the pros and cons between the two methodologies. In order to test their potential for conducting PFA, the team 3D printed two models of burnt bone fragments, to simulate the damage that might be encountered in a genuine investigation.

Modelled on an archaeological human femur donated by the University of Portsmouth, the replicated bone samples were cut and burned in a Gallenkamp Muffle Furnace at 600C for 3060 minutes. Each section of bone fragmented longitudinally, naturally, into at least two separate pieces, either during the burning process or during cooling. The two adjoining fragments were 3D imaged and printed to evaluate the techniques for their use in visualising and analysing the physical fit of burned bone fragments.

The SLS scanner used for testing was a Shining 3D EinScan Pro+, while the larger CT ZEISS Xradia 520 Versa scanner was also chosen, due to its simple setup and non-destructive process. After scanning, the fragments were 3D printed with a FFF Prusa i3 desktop printer, using PLA filament. The optimal print quality (0.15 mm) was selected, and infill levels were set at 0% to create a completely hollow print. PFA was then conducted on the pairs of 3D printed bone models, with accuracy determined on the basis of feature matching and alignment between the two fragments, as well as the haptic feel of the fit.

3D printing was found to preserve a high level of detail for both the CT and SLS models, and overall, the prints produced were of a sufficient quality to perform PFA. Based on the fit quality criteria set out by the team, the confirmation of physical fit was found to be easier using the CT prints compared with the SLS prints. Moreover, in all fragment pairs created, the CT models offered a closer and more robust fit, producing surface structures in greater detail, which was found to be of value in feature matching.

As a result, the researchers concluded that FFF 3D printing could be utilized to produce bone fragment replicas to a sufficient level of detail that either 3D scanning technique could be used. In addition, the team suggested that Selective Laser Sintering (SLS) 3D printing could prove to be a more efficient method of producing the models in future research, by negating the need for support structures used during FFF production. While it could ultimately prove more costly to implement, SLS printing would also result in a higher surface finish, according to the team. Additionally, the successfully reproduced bone fragments could open new applications for 3D printing in other aspects of the PFA process.

The application of 3D imaging and printing for PFA has many advantages compared with traditional methods. Virtual reconstruction of highly fragmented, fragile, and potentially embedded remains, offers an opportunity to generate full reconstructions without compromising the original bone fragments, concluded the researchers.

Furthermore, 3D prints from particularly small fragments or bones with micro-scale details can be isometrically scaled up, generating 3D replicas to visualise fit and perform PFA on items that previously would have been extremely challenging.

Additive advances in CSI

3D scanning and printing technology have been used in a range of ways to assist in CSI applications in recent years.

The Abu Dhabi Police Agency for example, have launched an additive manufacturing initiative to help solve crimes. Using 3D printing, the police force could produce dioramas that enable them to thoroughly assess a crime scene, or be summarily used to communicate a series of events in a court setting.

Police officers in Cascade County, Montana have started using FARO Focus 3D Laser Scanners to survey crime scenes. Capable of taking a full sweep of the scene, the 3D scanner potentially cuts down the personnel needed to record images by up to 80%.

Similarly, the UK-based West Yorkshire Police (WYP) force has installed a DeltaWASP 40 70 Industrial 3D printer at its Wakefield HQ. The machine is also used by its Regional Scientific Support Unit (SSU) in the recreation of crime scenes.

The researchers findings are detailed in their paper titled Reconstruction and physical fit analysis of fragmented skeletal remains using 3D imaging and printing published in the Forensic Science International journal. The report was co-authored by Amber J.Collings and Katherine Brown.

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Featured image shows the skull replicas that the research team produced using the CT scanning method. Image via Science Direct.

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UK researchers use FFF 3D printing to improve CSI analysis of skull fragments - 3D Printing Industry

Word is one of the San Francisco police brass who was in involved in managing crowd control during the recent George Floyd demonstrations took his police car home, only to have it stolen along with his riot gear.

Police spokesman Adam Lobsinger confirmed that on Wednesday. an off-duty officer reported that his unmarked vehicle had been stolen in the Marina District.

According to the police burglary bulletin, the gray, 2017 Ford Fusion was equipped with a police radio and that an SFPD jacket, a 26-inch baton and a riot helmet were inside the vehicle at the time of the theft. There were no firearms in the car, Lobsinger said.

The next evening the hot police car was found on the 2800 block of Vallejo Street in Cow Hollow.

No items appeared to be missing from the vehicle. The vehicle was towed to CSI (crime scene investigation) for processing, Lobsinger said. We are not releasing the name of the officer for officer safety purposes.

San Francisco Chronicle columnist Phil Matier appears Sundays and Wednesdays. Matier can be seen on the KGO-TV morning and evening news and can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call 415-777-8815, or email pmatier@sfchronicle.com. Twitter: @philmatier

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SF officer goes home after protests, only to have his car boosted. When it's found, nothing missing - San Francisco Chronicle

A man is set to appear in court in connection with an armed police incident which saw a woman left in hospital and officers use a taser.

Jamie West, 30, was arrested following an alleged attack on Ryhill Walk on the Overfields estate in Ormesby, Middlesbrough, on Sunday.

He charged on Monday afternoon with wounding and remanded in custody overnight, to appear at Teesside Magistrates Court on Tuesday.

Armed officers were called to Ryhill Walk at around 11.30am on Sunday after reports a woman had suffered injuries.

They found a woman with non-life threatening injuries "consistent with stab wounds", and she was taken to hospital by ambulance.

The force said officers used a Taser on a man to bring the incident to a safe conclusion.

The street was cordoned off until just before 2pm.

A crime scene investigation van was seen working inside a property.

The North East Ambulance Service told Teesside Live that the woman suffered injuries to her leg.

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Name of man accused of stabbing which saw armed police use Taser and left woman in hospital - Teesside Live

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On TV shows like "CSI," viewers get to watch as investigators find and collect evidence at the scene of a crime, making blood appear as if by magic and swabbing every mouth in the vicinity. Many of us believe we have a pretty good grip on the process, and rumor has it criminals are getting a jump on the good guys using tips they pick up from these shows about forensics.

But does Hollywood get it right? Do crime scene investigators follow their DNA samples into the lab? Do they interview suspects and catch the bad guys, or is their job all about collecting physical evidence? In this article, we'll examine what really goes on when a CSI "processes a crime scene" and get a real-world view of crime scene investigation from a primary scene responder with the Colorado Bureau of Investigation.

Crime scene investigation is the meeting point of science, logic and law. "Processing a crime scene" is a long, tedious process that involves purposeful documentation of the conditions at the scene and the collection of any physical evidence that could possibly illuminate what happened and point to who did it. There is no typical crime scene, there is no typical body of evidence and there is no typical investigative approach.

At any given crime scene, a CSI might collect dried blood from a windowpane without letting his arm brush the glass in case there are any latent fingerprints there, lift hair off a victim's jacket using tweezers so he doesn't disturb the fabric enough to shake off any of the white powder (which may or may not be cocaine) in the folds of the sleeve, and use a sledge hammer to break through a wall that seems to be the point of origin for a terrible smell.

All the while, the physical evidence itself is only part of the equation. The ultimate goal is the conviction of the perpetrator of the crime. So while the CSI scrapes off the dried blood without smearing any prints, lifts several hairs without disturbing any trace evidence and smashes through a wall in the living room, he's considering all of the necessary steps to preserve the evidence in its current form, what the lab can do with this evidence in order to reconstruct the crime or identify the criminal, and the legal issues involved in making sure this evidence is admissible in court.

The investigation of a crime scene begins when the CSI unit receives a call from the police officers or detectives on the scene. The overall system works something like this:

Every CSI unit handles the division between field work and lab work differently. What goes on at the crime scene is called crime scene investigation (or crime scene analysis), and what goes on in the laboratory is called forensic science. Not all CSIs are forensic scientists. Some CSIs only work in the field they collect the evidence and then pass it to the forensics lab. In this case, the CSI must still possess a good understanding of forensic science in order to recognize the specific value of various types of evidence in the field. But in many cases, these jobs overlap.

Joe Clayton is a primary crime scene responder at the Colorado Bureau of Investigation (CBI). He has 14 years of field experience and also is an expert in certain areas of forensic science. As Clayton explains, his role in laboratory analysis varies according to the type of evidence he brings back from the crime scene:

Depending on what scientific examinations are needed or requested, I may be involved in the actual "bench work" once the evidence is submitted to the laboratory. I have expertise in blood pattern identification (blood spatter), trajectory determination, serology (blood and body fluids), and photography. I also have knowledge in many other areas (firearms, fingerprints, questioned documents...) that may assist me at the scene. As a primary crime scene responder at the CBI, my role at the scene may involve one or more of my particular disciplines. While I would not do a functionality test on a firearm here at the laboratory, my role at the crime scene would be to collect the gun and understand its potential evidentiary significance.

Crime scene investigation is a massive undertaking. Let's start at the beginning: scene recognition.

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Introduction to How Crime Scene Investigation Works ...

Crime scene investigators are specialized law enforcement personnel, who apply their forensic science knowledge to the documentation of a crime scene. They collect and analyze evidence such as tire tracks, footprints, blood splatters, and many other elements of a crime scene to piece together theories about what occurred, the sequence of events, and how long ago they transpired.

Law enforcement agencies often lump together all sorts of personnel under the title of crime scene investigator, but for the purposes of this article, a crime scene investigator is a sworn peace officer with expertise in collecting and analyzing evidence gathered from crime scenes. An evidence technician is someone who gathers and processes crime scene evidence but is not necessarily a peace officer and is not involved in other aspects of investigating crimes.

Forensic science dramas on television have increased the popularity of crime scene investigation as a career. Those shows may also have affected the publics expectations of what crime scene investigators can bring to criminal prosecution. Many law enforcement personnel and prosecutors believe that such television programs have made jurors less likely to convict criminals when the prosecution does not present significant amounts of high-quality forensic evidence. Academic research has yet to prove the so-called CSI effect.

Crime scene investigators assist detectives in solving crimes by sorting through evidence and details to assist prosecutors in building a case. Their tasks include:

Crime scene investigators assist with collecting evidence and providing expert analysis of that evidence. They are often called as witnesses in criminal cases to explain their theories about what happened at a crime scene.

In a case, the crime scene investigator is called to the crime scene once law enforcement has already discovered or been called to the scene. The investigator assists in blocking off the scene from outside contamination, which could include helping uniformed officers set up barricades and caution tape and protecting evidence from damaging weather such as rain, sleet, hail, wind, sun, and snow.

The crime scene investigator identifies, collects, and inventories evidence at the crime scene. They take photographs of the scene and of individual pieces of evidence, while also ensuring that the methods used to collect and process the evidence will stand up to scrutiny by defense attorneys. A judge can disallow improperly processed evidence.

The investigator works with outside crime labs to analyze evidence that is beyond the departments capability to analyze. For example, a large police department might send bullet fragments to a state ballistics lab if the department does not have a ballistics experton staff.

The U.S. Bureau of Labor Statistics includes crime scene investigators under the category forensic science technicians. The salary for this career is as follows:

Payscale.com does provide the salary for crime scene investigators as follows:

Source: Payscale.com, 2019

Because crime scene investigators are sworn police officers, those wishing to become a crime scene investigator should research the requirements for becoming a police officer in local and surrounding jurisdictions, as these requirements may vary among jurisdictions. Generally, the following education, experience, and certifications are required:

To learn about the specific requirements for employment in your area, contact your local police department, the sheriff's department, and the state police to inquire about crime scene investigator qualifications at their facility.

Crime scene investigator positions are not entry-level jobs. They require the following skills:

According to the U.S. Bureau of Labor Statistics, 2017, the job outlook for crime scene investigators, included under the classification for forensic science technicians, is expected to grow 17% up to 2026.

Jobs are found in large police departments and state police organizations. Smaller departments do not have the manpower to devote a position solely to crime scene investigation.

This work requires traveling to areas that may be challenging to navigate due to difficult terrain, bad weather, or debris. In addition, crime scenes may be emotionally upsetting, gory, and difficult to view.

Crime scene investigators may work staggered day, evening, or night shifts and may have to work overtime because they must always be available to collect or analyze evidence.

People interested in crime scene investigation work should also consider the following similar career paths (along with median annual salary):

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Crime Scene Investigator Job Description: Salary, Skills ...