A new way to capture crime scenes

How 3D scanners, laser scanners and advanced cameras are revolutionizing investigation as we know it

Processing a crime scene--taking pictures, measurements, notes and more--is a laborious and pain-staking process. Anything that can make this faster, while at the same time improving accuracy, attention to detail and preserving the scene for later review or presentation to a jury, is a welcome addition to any police department.

Today, the technology mainly consists of 360 degree cameras and laser scanners, which accomplish different things, both beneficial to law enforcement. Police departments all over the world are adopted these technologies to varying degrees.

Meet a more robust camera

One of the real technological advances in law enforcement has been the development and adoption of high resolution cameras that are capable of taking a multitude of pictures in a very short time, cataloging the entirety of the crime scene, but with enough detail to make it a worthwhile tool for investigators and for presentation in court as well.

Some of the cameras are able to take 360-degree images, while others come close. All users agree, however, that these cameras offer tremendous ease of use, great flexibility and are a real technological breakthrough.

"The single most highly used piece of equipment at a crime scene is the digital camera,“ says Deputy Scott Lehmann, Dane Co. (Wisconsin) Sheriff’s Department. "It creates a permanent visual record of the crime scene in the state it was originally found. Digital cameras allow the investigator to see the image and make proper adjustments to ensure the perfect photo is taken.

"The old days of recreating a crime scene using a tape measure and recording the info on paper are gone!” he continues. “Thanks to advancements in technology, diagramming and recreating a crime scene is done with Total Stations, Panoramic cameras and now 3D Scanners.”

Panoscan specializes in digital imaging. The company's Mark III panoramic camera shoots 360-degree images in up to 580 megapixels. "The Mark II/MK-3 can achieve 360-degree captures that are better than the human eye; [they are] very good for picking up details and preserving evidence at a crime scene," says Ted Chavalas, president, Panoscan Inc. "The Panoscan camera is more of a visual presentation tool to present in court to a jury. When you show the images to a jury there is no doubt about what they are seeing. It depends on what the evidence is. Some evidence presents well visually, but other things you want are measurements, which is why we developed the portable 3D scanner. The Panoscan camera can do some measurements using photogrammetry, but it’s not as accurate as a 3D laser scanner.“

In 360/panoramic photos officers can create hot spots with a link that has extra information--close up, detail photos, measurement information and more.

“The benefit of using a 360 camera is when you are presenting it as evidence,” says Chris Dryden, commercial director, NCTech Limited. “If all you have is a standalone photograph with no context, it’s hard to get a sense of where it is in the scene. The 360 photograph provides the contextual relevance so you can experience what it would be like to be in the crime scene. They can move around, left or right, up or down ... you can do all that with the 360 photograph.

“If it’s particularly sensitive scene you can take the camera in, press 'go', leave it for a minute to do the capture, take it out and view the immersive images with minimal intrusion, and then decisions can be made from there.” he continues. “You can take multiple images as well. You can have all the information before the forensic guys go in. You can capture the entire scene digitally before it is disrupted in any way.”

Laser scanners

Different from the high resolution cameras, laser scanners produce a number of measurement points, called a point cloud, that create the 3D reconstruction of a crime scene. This point cloud data, when interpreted by the software, produces very accurate reconstructions of the crime scene with precise measurement data.

Laser scanners scan and measure everything at a crime scene, not just what investigators think is important at the time. The crime scene technicians set up the scanner and let it go to work, capturing everything so that if a witness comes forward a month down the line and a critical measurement is needed, you have the necessary data.

"Crime and crash scene reconstruction has definitely come a long way. Whether the person is on the scene or in the lab, new tools and technologies are providing investigators and analysts with faster, more comprehensive digital solutions," says Heather Parker-Fraser, marketing manager, law enforcement, FARO Technologies, Inc. "Depending on the size and available budget to an agency, crime scene tools can range from the very basic to the advanced. 35mm cameras, measuring devices like vinyl rulers, photomacrographic and L- scales, measuring wheels, CAD-mats and sketching templates are pretty basic tools that assist investigators with scene reconstruction. Getting more advanced, Total Stations and LiDARs offer a 'next-level' experience of collecting measurements and data. However, the most recent advancements are 3D Laser Scanners like those FARO Technologies manufactures. The beauty of the 3D Laser Scanner is that it does nearly everything the traditional tools do as well as the Total Stations. It measures, captures critical evidence, creates videos and, using post-processing software, allows you to place your scans into the computer and reconstruct the environment for 2D perspective, simulation or even high-end animation. A little pricier than the Total Station or LiDAR solution, but the range of a 3D laser scanner, speed of capturing the data, and ability to capture large scan areas, resolution of details, accuracy and sheer reduction in workflow and manpower that provide true ROI, is incomparable."

Portable scanners have made it possible to capture smaller crime scenes with more flexibility, at a lower cost than the more traditional laser scanners.

“The Panoscan Point Gun 3D scanner allows the crime scene investigator to recreate and diagram a scene faster and with more detail than ever before,” says Dane County’s Lehmann. “The Point Gun has been used for homicide investigations, motor vehicle accidents and to document bullet trajectory. The Point Gun records measurements and captures imagery faster than the traditional method using a tape measure and a two dimensional diagram. The three dimensional view adds a new and unique perspective to reconstructing a crime scene. It gives the viewer the ability to put themselves in the scene and virtually walk through, getting a perspective only those involved in the crime could experience.”

There is a trend towards more laser scanning in law enforcement, according to Panoscan’s Chavalas. “The first revolution was digital cameras, which allowed law enforcement to take many more pictures than before,” he details. “360-degree cameras have really started catching on, and now the latest trend is 3D laser scanners. Laser scanners are very good for outdoor accident scenes, but they are very expensive and they are cumbersome to move around. That’s why we focused on doing a handheld, less expensive scanner that’s easy to move around in confined spaces.”

Laser scanners make short work of capturing the necessary data at a crime or accident scene. “The most popular tool at the moment is the laser scanner, which can document crime and accident scenes by capturing millions of points at a time,” says Eugene Liscio from AI2-3D. “Once all the scans are aligned together, they create a full three dimensional environment that can be used for analysis and visualization. The laser scanner provides a completely different paradigm to traditional methods. The speed and amount of data captured is unsurpassed. Attempting to do this with traditional methods is simply either not possible or incredibly time consuming.”

Putting it all together

Some departments have both the panoramic cameras and the laser scanners, allowing them to create an amazingly detailed reconstruction of the scene. "Our two linchpins for major crimes are the Leica C10 Scanner and the IStar camera,” says Timothy Slusher, Crime Scene Investigator, Crime Lab, Montgomery County (TX) Sheriff's Office. “We’ve just recently acquired the IStar camera, prior to that we were using the scanner’s camera, but that was just OK quality. Right now, our protocol is that our investigators are all trained on the scanner and the IStar. They will go to a crime scene before anything is moved, we will take overall photographs, then we will scan the scene and mount the IStar from the same place as the scanner, and take the panoramic pictures. They will repeat the same setup anywhere from two to four scans. If it’s an outdoor scene, it could be as many as 12 or 14. We still take our own individual photographs. We still need the 8x10 or poster sized photos for court.

"We will then come back to the lab ... we have a dedicated computer that runs the Cyclone Leica software,” he continues. “The scan data is put into a dedicated file. We have to export it and the IStar images and we dump them into Color Cloud, the IStar’s stiching software. Color Cloud stitches the images and the point cloud, so you get very clear and crisp images from which you can do your measurements, fly-throughs, witness point of views and scene diagrams.“

The National Travel Safety Board uses a variety of technologies, dependent on the type of accident scene and the environment. “In some accidents, high resolution photographs are sufficient," says Kristin Poland, Ph.D., Senior Biomechanical Engineer, Office of Research and Engineering, National Transportation Safety Board. “In others, we may use the high resolution photographs in combination with photogrammetry techniques. For many accidents where a simulation may be performed or detailed crush measurements are required, we will use our 3D laser scanner. The laser scanner enables us to create a ‘virtual’ accident vehicle or accident scene by capturing a 3D point cloud, including color. The point cloud can then be viewed from any angle, sliced into sections, and measurements can be performed relative to undamaged sections relative to an exemplar vehicle. We also use a range of tools for vehicle handling, crash simulation, and occupant simulation.”

The future

The panoramic/360 degree cameras are very adept at high quality images in a fraction of time, while the laser scanners do a fantastic job of capturing measurement information and spatial relationships. The problem is that the cameras don't do very well at the measuring part, and the laser scanners fall down when it comes down to images.

Many people agree that the next step in technology is a combination product that does both things well, eliminating the need for both. That might be as far as five years away, but it's certainly on the horizon.

“I believe that 3D imagery of crime scenes will be the wave of the future,” says Dane County’s Lehmann. “Much like [how] digital cameras replaced film cameras, I feel 3D scanners will replace digital photography. I feel with the advancements in software, they will allow crime scenes to be recreated in such a manner that it will put the viewer physically in the scene. I have personally seen ‘The Cube,’ a 10 ft. x 10 ft. room that allows the 3D scans to be loaded and with the aid of special glasses, puts you into the scene. You have the capabilities of opening doors and walking down hallways within the scene. The days of transporting a jury to a crime scene will be over.”

The migration to digital has already begun. “Adoption of laser scanner technology is in full swing,” says AI2-3D’s Liscio. “In ten years from now, the majority of police agencies will be working with 3D technologies in some shape or form simply because of the value it brings to the table. Advances in color capture, portability, speed and accuracy will make these tools even more desirable since they will be flexible under many different environmental circumstances. Additionally, advances in processing and application-based software will allow police and investigators a means to do very specific analysis that would traditionally be painstakingly difficult. Also, the visualization of the data will be available in many different formats such as animations, virtual tours, virtual reality and 3D printing.”

The cost of these technologies is relatively high, but as more departments adopt, the technology will be seen as necessary and factored into budgeting. "Technology is advancing so quickly, I would think in five to 10 years you could see more officers and first responders as well as forensic labs equipped with 3D documentation and measuring devices as part of their standard uniform or workflow,“ says FARO’s Parker-Fraser. "It’s also not too far-fetched to see a day when a prosecutor or defense attorney can walk a jury through an actual crime or crash scene using immersive technologies. It is also our effort at FARO to make the software as simple and easy-to-use as the hardware, making for faster integration and adoption of new technology by all in the Public Safety realm.“

What’s needed is an all-in-one product, a one stop shop of crime or accident scene capture. “The future is definitely a product that does high res images and the scanner info,” predicts Montgomery County (TX) Sheriff's Slusher. “Someone will come out with this. It will be a push button deal where you push one button and it does it all.”

Luckily, despite all the technological advances and incredible advances, an officer will always be needed to interpret the data and actually solve the crime.