Author Topic: Right training proves essential for court presentations  (Read 24221 times)

Bob Galvin

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Right training proves essential for court presentations
« on: September 20, 2012, 02:41:52 PM »

Case study on MapScenes Trainer Joel Salinas by Bob Galvin

If your law enforcement agency has a total station still collecting dust in a room or closet because no one was ever trained on how to use it, don’t feel alone. Training on crash scene mapping equipment and evidence collection and diagramming software is available and does not require much time. It is an investment of your agency’s time and money that will reap big rewards.

Documenting a crash or crime scene with manual methods has far too many risks: potential inaccuracies, loss of data, insufficient data, missed evidence points, inability to share completed drawings. And, if your agency should have to re-examine a scene years later, unless the diagrammed scene and data points collected are on a computer, the task could be very difficult, even impossible.

Therefore, don’t allow these risks with manual mapping, but DO take some training on how to properly use mapping equipment once your department acquires it.

Even a used total station, usually priced much lower than a new one, will do the job, and the evidence collection and drawing software also accommodates most budgets.

Pursue Grant Funding To Acquire Equipment

Joel Salinas, a veteran law enforcement officer with the Vallejo, California, Police Department, would heartily agree. Salinas, who was a California Highway Patrol trooper for four years, and served as crash and crime scene investigator with Vallejo PD from 1988 to present, himself began drawing scenes with pencil and paper, later progressing to the AutoSketch and CAD-based software programs. In 2003, his department began using a total station, data collector and the MapScenes Evidence Recorder and Forensic CAD drawing software.

Today, in addition to his investigator’s job, Salinas teaches accident investigation courses and Forensic Mapping. With 1,200 to 1,500 combined crash and crime scenes mapped to date, Salinas is well suited for his instructor role. Although a fervent advocate of training on mapping equipment, Salinas knows it is not attainable for every law enforcement agency.

“The major challenge is funding to get this equipment and to get trained on it,” Salinas explains. Which is why he discusses grant funding options as part of his class instruction.

Get The ‘Right’ Training So Evidence Holds Up in Court

Equally important to Salinas, however, is once law enforcement agencies acquire their equipment and are being trained on how to use it, “Are they getting the right training?” he asks. A valid question. After all, some agencies buy a total station, for example, through a local survey shop. Therefore, they figure it makes sense to have the shop’s owner train them on the total station. Salinas’ concern?  “A surveyor may only show a law enforcement officer who will be mapping crash scenes how to set up the instrument, and how to measure a few points without any concept of what the law enforcement agency’s needs are,” Salinas offers. He recommends two weeks for students wanting to take his course, with one week devoted to mapping a scene with a total station and a second week on learning how to diagram a crash scene. If a law enforcement agency cannot afford a two-week course, Salinas can compress his instruction to one 40-hour week.

Above all, Salinas argues that a total station operator needs to learn some theory about how the equipment works and be able to provide testimony in court based on this. “If the operator is not able to answer questions about how he used his equipment and evidence collection software, he may not get his diagram into court,” Salinas said. “If there was any forensic analysis done based on the measurements taken with the total station, then this evidence also will not be admissible.”

Total Station Setup, Evidence Software Basics Taught

All students taking the forensic mapping courses must learn how a total station operates to the point where they can go out and map a scene and produce a drawing on their own. They are taught how to set up a total station and map a crash or crime scene. Students learn how to draw basic line-work, how to use basic features of the evidence collection and drawing software for editing their scene, and how to print it.

Students are given both a written exam and assigned a final project in which they must demonstrate proficiency. For every course taught, Salinas has seen his students successfully complete their exam and field mapping project.  And, he tailors each of his classes to match students’ needs.

Evidence Is Main Focus

Much of the crash investigation course focuses on types and scope of evidence. Specifically, in a crash scene, as evidence leads up to the heart of the scene, “there would be a nice set of skid marks,” Salinas says. Students in his course also need to determine if the driver involved in a crash reacted, and look for crash data and post-crash data: when the vehicles came to rest, where the debris field is, and any tire marks.

Of course, not every crash scene is perfectly laid out. There may be sparse evidence or none at all. “I’ve had cases as old as five years where there’s no longer any evidence,” Salinas recalls. “But the roadway configuration has not changed. As long as you have photographs and measurements or even total station data, you can bring that into your evidence recorder software and overlay it on the scene created in the drawing program after the fact,” Salinas said.

Aiding scene reconstruction these days is Google Earth. If a crash scene was documented with a Google Earth photo, a reconstructionist can see what day the photo was taken. “He can toggle back, in some cases, as far as 10 years to see what’s changed with the road,” Salinas said.

Versatile Library of Codes Needed

Salinas instructs students using an integrated solution that comprises a total station and the evidence collection and diagramming software. He considers MapScenes Evidence Recorder to be the most powerful mapping software on the market. One of the key features, he notes, is the ability to build a library of feature codes. For example, when mapping a crash scene the reconstructionist is going to need to code roadway features such as Edge of Pavement, Top of Curb, lane lines, double yellow lines, solid white lines, limit lines, etc.

“You can build a library of these feature codes based on abbreviated descriptions such as EP1 (Edge of Pavement 1), EP2, TOC, LL1, DYL1, DYl2, SWL1, and so on,” Salinas explains. “For each of these codes you can have the software assign them to a specific layer, have the software draw a particular line type with a specific color as needed. This saves time when editing and it also allows the user to easily recognize what it was that he originally mapped,” Salinas added.

Software Offers Point Detection, Error Display, Total Station Setup

MapScenes Evidence Recorder also offers point protection. When this feature is turned on, once the crash scene is downloaded, if any of the data points are altered a red flag appears. “This is very important for maintaining data integrity,” Salinas said.

Another key feature of the software is an error display when the total station is moved. “If I move the instrument from one location to another, the operator needs to know if there is a distance, elevation or angle error,” Salinas said. “These are displayed during the move instrument routine. Without this feature, the operator has no idea if the move was successfully performed in the field.”

Both Salinas and his students find MapScenes EvR helpful, too, for automated equipment setup. “You no longer have to go in and perform mathematical calculations to figure if you’ve set up the total station in the right place, or if you’re measuring evidence correctly,” Salinas explains. The MapScenes EvR software automatically walks the user through these setup steps, plus other ones such as naming the scene, height of the total station, height of the prism. “This is all important because anything you enter wrong is going to affect the elevation of your scene,” Salinas said.

The MapScenes Forensic CAD drawing program also receives strong praise from Salinas. An important distinction about it, he says, is that the software is a true CAD-based drawing program. “It draws and saves in the most common and interchangeable format, which is DWG,” Salinas said. “Plus, it uses the IntelliCAD drawing engine, which is virtually identical to AutoCAD in the commands and functions.”

Customized Symbols, 3D Modeling Big Advantages

Many crash scene drawing programs have limited symbols libraries and modeling capability. Not MapScenes Forensic CAD. For example, if Salinas needs to model traffic signals, buildings, or vehicles, he can do so in Forensic CAD. “I don’t have to settle for using the symbols that came with the program,” he said. “I can build my own.”

One of the most unique features in Forensic CAD for Salinas and his students is 3D modeling. Once a scene is mapped in 3D, the EvR software allows the user to rotate the scene around on the data collector computer screen so he can be
sure he’s captured all critical evidence data.

Drawing a crash scene in 3D is not always required. In fact, the need for a 3D diagram often emerges from what initially is a 2D diagram that may not fully represent possible events leading to a crash or crime scene. “We recently had an officer-involved shooting for which a 2D drawing was created,” Salinas said. “But we realized we would need a 3D model to represent how that scene looked both to the officer and the suspect.”
As helpful as technology is in the instruction Salinas offers to his students, there is a wide swath of capabilities to learn. So, there will always be a learning curve to forensic mapping regardless of which software is used. Salinas simply feels students need to have a desire to learn as well as the aptitude for mapping and drawing crash scenes. “Most importantly, the students need to get out and practice with the equipment and software,” Salinas said. “Crash and crime scene diagramming is all about field based proficiency. It’s a use or lose skill.”