More and more agencies are employing surveying equipment such as total stations to record data for 3D crime scene imagery.
Since the earliest days of trial by jury, detectives have been searching for new ways to help jurors visualize crime scenes. In this pursuit, law enforcement quickly adopted photography and hand-drawn diagrams to create two-dimensional representations of crime scenes.
These basic courtroom graphics have always been, well, as the term two-dimensional indicates...flat, lacking vertical depth. But not anymore.
Using new computer and photographic technologies, investigators can create diagrams with complex 3-D surfaces and immersive 360-degree images. Such high-tech representations of crime scenes allow for much more accurate presentation of bullet holes, blood spatter, and other evidence that's hard to document with 2-D methods.
Since visual documentation is considered one of the most important types of evidence presented to a jury, the details of a diagram-or lack of them-can dramatically impact a jury's perception of the chronology and probable events surrounding the crime, which can ultimately impact the verdict.
So how do you recreate a crime scene in 3-D? Well, unless you want to make a diorama, you'll need a computer and some special software. Solutions range from about $500 to more than $60,000. How much you spend will depend on the complexity of the equipment and software that you want to acquire and the desired level of detail in the final product. The most cost-effective solution is to purchase diagramming software that accepts "Z" axis or vertical measurements.
To use these tools, CSIs or detectives at the scene use a tape measure or inexpensive laser measuring device to manually measure length, width, and height of the location and the evidence. These data points are entered into the software by hand then used to create the 3-D diagram.
If you want to spend a little more money for greater precision, you might want to integrate a sophisticated measuring device such as a total station (a surveyor's tool) to electronically capture distance information.
Using a total station, you can accurately measure distances and angles, recording 3-D data. The total station is connected to a small device called a "data collector," usually a PDA. The measurements are stored electronically on the data collector and can be automatically transferred into a 3-D software program. The advantages of working with a total station and a data collector include increased automation, faster measurement, and many more measurement points, yielding a more detailed diagram.
Another option for obtaining 3-D measurement is through the use of photogrammetry, the science of extrapolating 3-D measurements from 2-D photographs. Software advances have made this process easier, considerably less expensive, and more accurate than ever. And photogrammetry has also been merged with immersive imaging to provide a unique view of the crime scene along with precise 3-D measurements.
Immersive imaging has been used in real estate sales for years, yet only recently have police departments begun to use this technology. An immersive image provides a 360-degree view of the scene that the viewer can scroll around; it's almost like being in the crime scene. This is especially powerful when combined with 3-D measurement.
The following is a collection of some of the most widely used tools for 3-D diagramming:
Crime Zone from Beaverton, Ore.-based CAD Zone is one of the most popular forensic diagramming software packages on the market. CAD Zone has been developing forensic software products for more than a decade and it shows in the quality of Crime Zone.
Any cop who is moderately computer literate can easily create professional 2-D and 3-D crime scene or crash scene diagrams and models with Crime Zone. The program is surprisingly easy to learn, and not just the basics either. It takes far less time than you'd think to master this software. The interface is intuitive and the symbols library is complete, containing just about every type of weapon and piece of evidence you can imagine.
A unique feature of Crime Zone is its ability to create a 3-D model from a 2-D diagram with the click of a button. The 3-D model includes all the 2-D measurement information and can be viewed from any perspective. Additionally, measurements can be entered in baseline or triangulation form, making it far easier to place evidence in the diagram. Small details count, like articulated joints on the figures that allow the user to ensure the body is accurately portrayed in the diagram.
Departments using a total station can purchase Crime Zone with Pocket Zone for $995. Pocket Zone is data collection software that can be loaded on the handheld computer of your choice and connected to a laser measuring device. The 3-D measurement data is easily imported into Crime Zone, greatly speeding up the workflow. Also, Pocket Zone is the only data collection software specifically designed for law enforcement, not surveyors, so it's easier to use than many of its competitors.
The DeltaSphere 3000 3-D scanner and SceneVision 3-D from Chapel Hill, N.C.-based 3rdTech are two of the most amazing law enforcement products that I've ever seen. The DeltaSphere 3000 3-D scanner is a high-speed scanning laser rangefinder that's kind of like a total station on steroids. By that I mean it's capable of taking more than 25,000 measurements per second.
3rdTech’s DeltaSphere is a high-speed laser scanner that can record 25,000 measurements per second.
Users set up the DeltaSphere 3000, and it automatically scans the scene, taking millions of precise measurements along with digital photographs. 3rdTech's SceneVision 3-D software then combines these data points and digital photographs to create a high-resolution digital recreation of the scene. This diagram can be rotated around any axis and viewed from any desired perspective. You can zoom in or out and add closeup photos of specific evidence. In addition, extremely accurate 3-D measurements are possible of any items in the scene and tools are included for bullet and blood spatter trajectory.
SceneVision 3D from 3rdTech takes the data from the company’s DeltaSphere camera and creates immersive 3D environments.
The effective range of this unit is about 40 feet. You really need to see the resulting diagram on a computer to fully appreciate the capabilities of the DeltaSphere 3000. The DeltaSphere 3000 creates the most accurate and detailed 3-D diagram I've ever seen. Price is around $40,000, depending on the exact configuration.
DeChant Consulting Services of Bellevue, Wash., offers a unique photogrammetry software package called iWitness that's designed specifically for crime scene and crash scene measurement. It's simple to use but very powerful.
Here's how iWitness works: Take three digital photographs of the same scene from three different angles. At the scene, measure one distance visible in all three photos. Next, import the images into iWitness and mark six corresponding points that are visible in the images. The software automatically orients the camera in 3-D space and processes the data to provide accurate 3-D coordinates of any points marked in the scene.
The data from iWitness can be directly imported into a variety of computer-aided drawing (CAD) systems, including Crime Zone. The bottom line: from one measurement and three photos iWitness, which retails for $895, can accurately determine 3-D distances of the crime or accident scene.
The SpheroCam HDR distributed by Linear Systems of San Bernardino, Calif., is truly on the cutting edge of technology. This system combines a high-resolution (up to 50 million pixels), high-dynamic-range camera with precise 3-D photogrammetry.
The details of this crime scene were captured with the SpheroCam HDR, a high-dynamic-range, high-resolution camera.
To use the SpheroCam HDR, you place the specially calibrated digital camera system (with a 16mm fisheye lens) atop a tripod in the center of a crime scene. The camera then rotates 360 degrees, capturing everything from the floor to the ceiling.
The resulting immersive image allows the user to pan up and down and left and right. A zoom tool allows the user to look closely at evidence in the scene. The unique feature of this system is that any item can be accurately measured in 3-D space by simply dragging a slider between two points.
Multiple scenes or rooms can also be linked together by hotspots to create a "virtual reality" tour of the crime scene. The included software is intuitive and features image encryption and user verification to ensure the veracity of the images.
This advanced system is not cheap. It's priced from $45,000 to $70,000, but you may find it worth the price, especially when you consider its flexibility.
MapScenes from Canada's MicroSurvey is marketed as a "Complete 3-D scene diagramming tool." The software is designed for both crime scenes and crash reconstructions, and is sold in two versions, Pro and Lite.
The Pro version of MapScenes sells for $1,395 and is designed for agencies using total stations or other electronic measuring devices. MapScenes Pro is designed to be used in conjunction with MicroSurvey's Evidence Recorder Pro ($995) to collect electronic measurement data and transfer it into your computer.
MapScenes is a powerful diagramming tool that allows for animated viewing of the diagram in 2-D or 3-D. The included symbol library contains more than 7,000 items, the most of any diagramming software. And digital photographs can be linked to the diagram to show specific details.
All of its features could lead you to believe that MapScenes presents users with a steep learning curve, but the included tips, manual, and training movies really help get you up to speed.