Since 2018 I have had the opportunity to use the Z+F Imager® 5016 laser scanner, forensic kit, and Z+F LaserControl software for forensic crash reconstruction. I have been in the field of crash reconstruction for 27 years. First, with the Pennsylvania State police followed by my private firm Thierwechter Collision Forensics. I was first trained in scale drawings done by hand, progressed to total station measurements with CAD drawings, to exclusively using the Imager® 5016 for all scene documentation and vehicle scanning.  With its 360 meter range (1180 feet), accuracy, onboard HDR camera with SmartLight for capturing color data day or night, and in-field registration, the Imager® 5016 is the perfect tool for preserving a crash scene for further analysis and measurement. LaserControl Scout and Office versions allow for optimized registration and colorization in the field during the ongoing project.

The workflow that I have settled into over the years is this; first, reporting to crash site, whether still active or after it has been cleared. Once there, I determine the necessary area to be scanned. A typical crash site will require anywhere between 8 to 20 scans, depending on its scale. Each scan location will be scanned, typically with a density of 6.6mm at 10 meters, and with the HDR camera feature to capture color data along with the point cloud. Before leaving the site, I will make sure that I have captured everything necessary and that the project has registered using the cloud to cloud registration algorithm. After that, it is back to the office where the project can be fully processed, filters applied, colorized if not done earlier, and necessary cleanup performed. Once that has been completed, the scans are exported in e57 format and imported into Veesus Arena 4D Data Studio. In Veesus a variety of measurements can be performed and displayed on screen. Veesus also allows for the creation of line work which can be exported in dxf format for use in CAD programs. Yes, I still use CAD drawings. I find their clean simplicity to be beneficial to the attorneys I am working for and to the juries to whom the complexity of a crash is being presented. The scan data can also be used in crash animation software.

In my private work I take on projects with District Attorneys for criminal prosecution and also civil cases, generally wrongful death and personal injury. I thought some day I would be writing a similar article celebrating how the Z+F Imager® 5016 and the data it captures has successfully survived a Frye or Daubert challenge and been accepted in court. To date, I have had three criminal cases, two Homicide by Vehicle while DUI, and one Recklessly Endangering Another Person. In all three cases, the Z+F Imager® 5016 was used to capture scene and vehicle data. All three cases were resolved with guilty pleas and the data was not challenged. I have used the Imager® 5016 in six civil cases where the data has not been challenged. I have also used the scanner in cases where the final decision was not to seek prosecution because the facts did not warrant it.

The results of this phenomenal tool speak for themselves. The detail, accuracy, and range of the scanner are unparalleled. I would use no other tool than the Z+F Imager® 5016 for crash and crime scene documentation.

References:

Criminal Cases
Commonwealth v. Dougherty CR-0001149-2021, Cumberland County, Pennsylvania
Commonwealth v. Marchese CR-0001186-2021, Cumberland County, Pennsylvania
Commonwealth v. Slonaker CR-0003373-23, Chester County, Pennsylvania

Civil Cases
Steigerwald v. Rhone and Woodfield Inc. 18-CV-02390-YK, Lebanon County, Pennsylvania
Wetzel v. Beiler, Wolfe, and Putnam No. 2019-295, Centre County, Pennsylvania
Wiggins v. Pratt CI-21-00375, Lancaster County, Pennsylvania
Johnson v. Lentz v. BARTA 24-02217, Berks County, Pennsylvania
One action still in litigation.
One action settled prior to filing

The first example shows a three vehicle crash involving a farm tractor, pickup truck, and a passenger car. I was called into the case well after the crash occurred. The scene (over a 1000 feet of roadway) was scanned with 21 individual scans. The vehicles were scanned in an impound lot and were then imported into the scene project.

The second example was a three vehicle crash involving a pickup truck, and two passenger vehicles, one was towing a trailer with a boat. The boat became dislodged in the crash and can be seen at final rest. The trailer was moved back by first responders. Note how well the tire marks and police paint markings were captured in the image above. This was an active scene that I was called to. There were a total of ten scans of the scene with vehicles in place.

This example is where a motorcycle ran into the rear of a commercial vehicle. Five scene scans were performed. The commercial vehicle was scanned in storage. An exemplar motorcycle was used as the original was destroyed beyond use.

The next example is where five scans captured an intersection for the purpose of creating a CAD diagram for video time distance analysis.

Video Still

The last example is a pedestrian crash. The vehicle was scanned while in police custody and the scans were imported into the scene. Two weeks after the crash the roadway was shut down and evidence markers were reset. The original paint markings were still visible. Six scene scans were taken, and the roadway was reopened within an hour. The investigation revealed that no charges against the driver were warranted.