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Chapter 14. Figure 14.1 Note vertical and axial reference lines for plotting the location of bullet defects and measuring azimuth and inclination angles of bullet paths.
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Figure 14.1 Note vertical and axial reference lines for plotting the location of bullet defects and measuring azimuth and inclination angles of bullet paths.
Figure 14.2 An artificial reference line is established by snapping a chalk line at known distances from the axles of the vehicle. Colored masking tape is applied to the line for better visualization, as seen here
Figure 14.3 A 4-foot level, measuring tape, and plumb bob are used to accurately plot the location of bullet holes using the reference line. Measurements taken using this method can generate accurate scaled computer-aided design (CAD) diagrams of the bullet paths through the vehicle that can be imported into other scaled CADs of the shooting scene.
Figure 14.4 A protractor is employed to measure azimuth angles of various bullet paths represented by probes in this vehicle. Note the longitudinal reference line on the ground and a parallel reference line using string between two tripods that can be slid up and down to the various heights of the probes for convenient/accurate measurement with the protractor.
Figure 14.5 Computer-aided designs illustrating accurate to-scale reconstructions can be prepared from hand-drawn diagrams when appropriate. In this example, a scaled CAD of bullet paths in a vehicle prepared by the author was imported into a scale CAD of the entire shooting scene prepared by the investigating police agency. The bullet paths were then extrapolated throughout the scene for further study.
Figure 14.6 Vehicles present additional challenges to the reconstruction of bullet paths due to their mobility, flexible suspension, and travel over varying terrain when receiving fired bullets. Bullet paths registered in vehicles are relative only to the vehicle at the moment it is struck in whatever orientation it may be in, given the previously mentioned conditions. Therefore, it is important to document the orientation of the vehicle while still at the shooting scene to account for as many variables as possible. In this case, the author used a laser level device on a short tripod as a reference beam relative to the height of the edge of a roadway to document the longitudinal inclination of the vehicle body using the axles as reference points.
Figure 14.7 The lateral tilt of the vehicle is measured using an inclinometer at the scene to document its orientation relative to the terrain, which can later be used to correct estimated bullet paths determined after the vehicle is towed.
Figure 14.8 The single entrance hole created by this shotgun wound exhibits indications of the beginning of individual pellet holes at the margins. This is generally typical at distances of approximately 2–3 feet. In this case, the author concluded that the muzzle-to-wound distance was approximately 2 feet after comparing the morphology of the wound pattern to test patterns produced at known distances and angle using the responsible shotgun and ammunition.
Figure 14.9 Telltale slap marks were observed around the periphery of an entrance wound to the decedent's forehead involving a .410-gauge shotgun loaded with a shotshell containing #4 shot and a plastic tripetal combination wad. Powder stippling/powder tattooing can also be observed around the entrance wound. Photo printed with permission of Faye Springer.
Figure 14.10 A plastic tripetal combination wad used in shotshells fired in suspect shotgun. Photo printed with permission of Faye Springer.
Figure 14.11 Using the suspect shotgun and the same ammunition, test patterns were produced with very similar slaps marks and gunpowder patterns at distances between 18 and 32 inches and were used as a basis to estimate the muzzle distance of the shotgun from the decedent's head at the instant the fatal shot was fired. This pattern was produced at a 24-inch distance. Photo printed with permission of Faye Springer.
Figure 14.12 Note the impression of a plastic wad in this wooden sign among several buckshot holes. Such impressions can be an indicator of distance traveled in addition to the pattern of the shot pellets.
Figure 14.13 This illustration provides a general guideline of maximum distances that shotshell components can travel. These distances will vary to some extent depending on the type of shotgun, the length of the barrel, and the type of ammunition used. The reader is cautioned that these distances are approximate in nature and should be used only as a general guideline in estimating muzzle-to-target distances in the field. Testing with the responsible shotgun and ammunition used, if available, should be conducted whenever possible to ensure the most reliable estimate of muzzle-to-target distance.
Figure 14.14 Shotshells containing shot pellets fired from rifled shotgun bores (normally designed to fire slugs) produce dramatically different patterns from those fired from smooth bores. The patterns formed resemble “hollow circle” or “doughnut”-like patterns with significantly more spread (right) at the same given distance as patterns from smooth bores (left), as seen in this example of buckshot fired into a wooden gate. Also, note the impact of shot wads (arrows).
Figure 14.15 Shotgun loads fired at flat surfaces other than perpendicular angles will produce an elliptical pattern that can be used as a basis for estimating angle of impact by dividing the oval width by the length and calculating the arc sin value of this ratio. Note the characteristic pinch points on the left edges of the defects produced by nine buckshot balls and boat-wave-fractured edges of the paint surrounding them, indicting a left-to-right direction of travel at a low incident angle.
Figure 14.16 Finished drawings such as the illustrated bullet path in this residence can be prepared from a hand-drawn sketch but are not essential to the successful outcome of the shooting scene investigation. They can, however, be quite useful for informing a jury in court. The author prepared this projection diagram for this purpose with an easy-to-use Broderbund Home Architect 3D drawing program and then annotated it using PowerPoint.
Figure 14.17 This finished diagram illustrates various bullet paths in a vehicle prepared by scanning a generic vehicle diagram into PowerPoint and using the simple drawing tools of this software program to annotate it.
Figure 14.18 Elevation diagrams provide height perspective views of a shooting scene and are an essential form of documentation for reconstructing bullet paths. This example depicts several bullets that have entered at the rear and right rear of a station wagon and one bullet that has deflected off the roof of the vehicle.
Figure 14.19 This 3D perspective diagram of the bullet path in a shooting scene was prepared with the Broderbund Home Architect 3D drawing program and then annotated in PowerPoint. Three-dimensional drawing programs allow the reconstructionist to view the crime scene in any perspective.
Figure 14.20 This three-dimensional rendering from an aerial photo taken over the scene of a shooting incident was produced using the Canoma software program. This software allows the reconstructionist to create a 3D model of a shooting scene from a 2D photograph. The model can then be manipulated into any viewpoint and zoomed in and out to any distance. An animated “fly-through” of the 3D scene can also be produced using this software. These models can also be helpful for reconstructing specific viewpoints of key witnesses/participants involved in a shooting incident to either corroborate or refute their statements.
Figure 14.21 This photo depicts a patio area just outside of a kitchen doorway where a fatal shooting occurred with the use of a shotgun. Critical to the case were the position and orientation of the victim and shooter at the moment the fatal shot was fired. The male victim's dress jacket and personal items are observed in the foreground. An expended shotgun shell is just inside the doorway. Spattered, dripped, and trailed bloodstains are also evident.
Figure 14.22 The author prepared this perspective view of the most probable position/orientation of the shooter and victim at the instant the fatal shot was fired after (1) investigating/processing the original shooting scene, (2) examining numerous items of evidence, (3) reviewing the autopsy report, (4) conducting numerous tests with the shotgun and ammunition used, (5) interpreting numerous bloodstains, and (6) considering statements made by witnesses. The shooter and victim were created using Poser superimposed over this perspective view of the patio area created with the Broderbund Home Architect 3D drawing program.
Figure 14.23 A portion of jacketing recovered from the perforating leg wound of a participant during a postmortem examination was matched physically to the bullet recovered in the floorboard of a vehicle after having passed through the driver's seat cushion. This combined information made it possible to position the gunshot victim in the vehicle at the time the wound was received.
Figure 14.24 Autopsy photographs depicting probes inserted into the wound track can be used to estimate the horizontal and vertical angles, provided that they have been taken from the proper perspective. The perspective of this photo is taken at eye level and is perpendicular to the plane of the decedent's back, making it possible to estimate the angle of the bullet path.
Figure 14.25 In this case, the pathologist narratively described the bullet paths but did not provide any illustrations or photos of the bullet paths. In order to obtain a clearer understanding of the various bullet paths, the author plotted the bullet paths using this anatomical diagram based on the pathologist's narrative descriptions of the wounds received by the decedent. The author then presented the diagram to the pathologist to verify the accuracy of the represented bullet paths before drawing reconstructive conclusions from this source of information.
Figure 14.26 This anatomical model, produced by the author using Poser, depicts a decedent who suffered three gunshot wounds. The model can be viewed from any viewpoint using the software program and images can be exported for illustration and study. In this case, the left arm of the victim was raised at the instant a bullet passed through the triceps muscle and into the left chest (black probe depicted). When the decedent is lying on the autopsy table, this observation is not apparent, but it can be illustrated effectively using such models.
Figure 14.27 A police officer was shot through the pelvic region while attempting to apprehend a suspect wanted for several murders. The bullet was not removed from the officer for medical reasons, and it became important to know if the officer was shot by the suspect or a fellow officer during the incident. This X-ray depicts a bullet that transversed the hips of the wounded officer and lodged in the right hip area. The X-ray was taken in such an orientation that a clear profile of the bullet shape could be seen.
Figure 14.28 Side profiles of the bullets associated with ammunition used in the suspect's gun and police officer's service weapons were compared. The suspect was using ammunition with full metal jacketed round-nose bullets, whereas the police officers were using jacketed hollow-point bullets. The profiles of sample bullets from these two sources of ammunition were compared directly to the profile of the shadow created by the bullet in the X-ray. The author was able to eliminate the police officers' ammunition but not the suspect's ammunition.
