Author Topic: The Perfect Tool for Drawing 3D Indoor Shooting Scenes  (Read 37829 times)

Bob Galvin

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The Perfect Tool for Drawing 3D Indoor Shooting Scenes
« on: November 24, 2011, 03:28:07 PM »

An electronic diagram may well be the lynchpin of a crime scene investigation. How? First, the diagram is the culmination of a painstaking process of evidence collection that is accomplished with photography, videography, data mapping via total stations or other means. Moreover, the diagram shows the relationship of the evidence to the most likely chain of events. Second, the diagram is the most compelling tool in a courtroom for explaining the events and evidence to jurors and judges unfamiliar with the crime scene.

While crash and crime scenes are vastly different from each other when it comes to evidence, the evidence is crucial. Frequently, a crash scene resulting in death becomes a crime scene. Therefore, having a versatile scene measuring and documentation software is also essential.
For Brad Joice, owner of Forensic Mapping Services in Barrie, Ontario, Canada, the ability to map crime scenes, especially indoors, and in 3D, has become pivotal to his court presentations. Without it, making such presentations with high credibility and acceptability would quickly become a huge challenge. "The evidentiary and probative value of that three-dimensional diagram is much stronger for an indoor crime scene than an outdoor scene," Joice explains. "For instance, we can measure a shooting scene with the 3D aspect in mind and create trajectory analysis. We can show that in court."

Low Crime Rate, Yet Indoor Shootings Persist

In addition to operating his forensic mapping business, Joice also is an investigator in the Forensic Identification Unit of the York Regional Police (Newmarket, Ontario, Canada). Which has enabled him to see some interesting trends, one of which is that crime in Canada is low. "We have maybe eight to ten homicides a year," Joice said of the crime incidents his law enforcement agency handles. "And 30 percent of those may involve shootings." The York Regional Police has 1500 sworn officers, and covers just over 800 square miles of a population of more than one million people.

Although the crime rate is low, Joice nevertheless knew from the start that he needed the best possible tools to measure crime scenes for eventual court presentations. He found them in the MapScenes EvR and Forensic CAD software, which he finds particularly crucial for mapping shooting scenes.

"Where the true value of the software comes in is when we're dealing with the three-dimensional representations," Joice said. "That stems from shooting scenes because that's where we can get a true appreciation of having a three-dimensional drawing---when  you see what the trajectory of a gun shot is in 3D."

Scenes in 3D Offer Most Detail, More Precise Measurements

Joice uses the MapScenes software for 3D shooting scenes more than any other types of crime scenes. Most of the other scenes are mapped and measured in 2D. But it is the 3D scenes that provide the detail that will provide a court the clearest understanding of a crime scene's history. "If we're drawing a scene in 2D, the approach may be significantly different," Joice explains. "It makes a difference in the number of points you're going to map, and the number of measurements you're going to take." Far more points must be measured for a 3D versus a 2D drawing, he adds.

"This is where I think MapScenes pulls out ahead of the competition," said Joice, who gives an example. When drawing in 3D, if you're measuring, say, a wall, you can measure where the wall is in 2D.  Say it's an eight-foot wall ceiling. You can draw that wall as an eight-foot ceiling. Although it's an eight-foot ceiling, not all of the corners may be 90 degrees. The wall may be at a slight angle, and might not be perpendicular.

Joice argues that if you just take one point on that wall, in CAD, it will give a height of eight feet and that is the room. "Some software programs would draw this wall as perfectly straight and vertical," Joice said. "The reality is, show me a house out there with walls that are perfectly straight, vertical, and perfectly square."

The MapScenes software is able to account for these measurement variances and give a true representation of the wall dimensions. This is why the software is so integral to Joice's crime scene reconstructions involving 3D shootings. "It's critical we have the angles of those walls and the bullet holes as precise as we can get it," he said. 

Total Station, Laser Meter Link Data With Software

When reconstructing a crime scene, Joice uses a Sokkia 530R3 total station, which can measure in a reflector or reflectorless mode. Reflectorless mode, Joice says, is essential for mapping crime scenes because a lot of what he is measuring cannot be done with a prism or is simply impractical. Another tool Joice uses is a Leica Disto laser meter, which is designed to measure distances. "It integrates with Evidence Recorder the same way a total station would," Joice said. But the Disto only measures two-dimensional values, which means it will not give an elevation of any distance.

Therefore, Joice said, if he's going to map a homicide in a house, and the main part of that scene occurred in the bedroom, he would set up a total station to measure the bedroom because it's very accurate and provides the elevation of every mapped point being measured. For the rest of the house, Joice said he would use the Disto because he can just walk around from room to room and the device will automatically feed the measurement data into Evidence Recorder.

Bullet Trajectory Shows Range of Victim Positions

For an example of how this technology works, Joice cites a shooting scene he investigated where the victim was shot in a bedroom of his house. There were two males in the bedroom, and at some point a gun was fired. The victim had a fatal gunshot wound to the chest. The bullet traveled through the victim, exited on his side, then passed through the wall in the first bedroom and into the adjacent bedroom. The bullet kept traveling into the wall on the opposite of this second bedroom.

Joice measured both bedrooms in 3D, then was able to draw the trajectory from the first bedroom through the wall into the other bedroom and was able to place where the victim was at the time the weapon was fired. Forensic CAD was helpful for creating the diagram that showed this trajectory, Joice noted. "It was a valuable tool in court because although we weren't able to give the victim's exact position, I could give a range of positions, such as showing how the victim had to be between two specific points at the moment the shooting occurred," Joice said. "The drawing software narrowed down his position to about a four-foot area along the trajectory path of where the victim had to be when the gun went off."

Software Offered Extra Benefits

In addition to the diagram generated with Evidence Recorder and Forensic CAD, Joice noted that MapScenes Capture gave some extra tools needed for creating some 3D views. For example, he said, when Joice and other investigators were trying to place a 3D object on a floor, MapScenes Capture has a tool to make micro adjustments to that object, which could be a gun or a chair. "We can place that object at any angle or give it a very precise placement in the scene using some tools in Capture," Joice said. "This can still be done in Forensic CAD, but Capture can do it more simply."

Using EvR, Joice can view a basic outline of his drawing as evidence points are captured. "That's crucial for us, for any scene," Joice said. "It allows us to see what we're measuring or what we're not measuring---like the corner of a  house."

'Seamless Integration'

What Joice values most about his crime reconstruction software tools is what he calls a "seamless integration" between Evidence Recorder and Forensic CAD. "When I'm mapping and measuring a crime scene, I can see it being drawn," Joice said. "When I download that data collector into Forensic CAD, that drawing is two=thirds complete for me just by downloading it. And my line work is there," Joice adds. In addition, no assumptions must be made about straight/vertical walls or 90-degree corners. "I'm  measuring those with a total station and drawing them in Forensic CAD." Therefore, the software is drawing from actual data. "To me, that's a huge benefit, and a huge issue for the court," Joice said. "And this speeds up the process of drawing and producing the final drawing."
« Last Edit: November 24, 2011, 04:25:36 PM by Bob Galvin »


  • Guest
Re: The Perfect Tool for Drawing 3D Indoor Shooting Scenes
« Reply #1 on: April 23, 2012, 11:56:27 PM »
I like this tool. Really looking awesome. It has some extra and useful  functions. And the pictures are also clear.


  • Guest
Re: The Perfect Tool for Drawing 3D Indoor Shooting Scenes
« Reply #2 on: April 30, 2012, 05:41:05 AM »
Leave the picture but tell me it can be operate by any operating system.