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Law Technology Today

2024

Using 3D Modeling, Photogrammetry, and Laser Scans When Surveillance Footage Isn’t Enough

David Notowitz

Summary 

  • When surveillance footage isn't enough, 3-D modeling, laser scans, and photogrammetry can help attorneys decipher what really happened at the scene of an incident (criminal or civil).
  • The laser scans must be taken right away, or else the scene could change, and you wouldn't get an accurate reading.
  • 3-D models can be shown in court on a screen to prove a case.
Using 3D Modeling, Photogrammetry, and Laser Scans When Surveillance Footage Isn’t Enough
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It seems like cameras are all around us, capturing our every move. From Ring doorbells to traffic cameras to surveillance in businesses and on the streets, we are constantly being monitored and recorded. There are cameras installed in moving vehicles, from police cars and buses to cameras on private cars; the newest models of Tesla cars have an astounding eight cameras.

When it comes to crimes and civil issues, the footage captured on these cameras can prove to be indispensable. They might show someone committing a crime or otherwise doing something wrong such as driving dangerously or not properly mopping a floor, helping attorneys build a case.

But what do you do when surveillance footage doesn’t tell the full story? Of course, even footage has its limits. For example, you can’t tell someone’s height by looking at them on tape. You cannot determine how fast a car is going or which car struck a person if there are multiple vehicles involved in a crash and all the angles aren’t shown.  

There’s also the issue of footage being grainy or not totally clear; perhaps a tree is blocking the view, or there was some other type of interference that makes it difficult to decipher what happened.

If there is a question regarding footage – maybe your client said that wasn’t him committing a crime in a video, or it’s not easy to see which car hit a pedestrian – you can use laser scans, 3-D modeling, and photogrammetry to help figure out the truth.

How Photogrammetry, Laser Scans, and 3-D Modeling Work

Photogrammetry is the scientific measurement of distances, speed, and heights using clues embedded in still images or frames extracted from videos. Attorneys can reach out to forensic experts to assist them with laser scanning a location and then creating a 3-D model on a computer. This will effectively reconstruct a crime or accident that happened instead of relying on flat surveillance footage.

Using a laser scanner, a forensic expert will scan the entire area. Depending on the location, this could include the street, the sidewalk, the inside of a hotel room or lobby, or an automobile. The most commonly used laser scanner, a FARO, sits on a tripod and does a 360-degree spin as it’s firing a laser and mapping millions of data points. Depending on the location and needs of a case, an expert may take three to thirty laser scans of one location and then combine them all into one 3-D model using software that connects the scans together. The expert can then match individual frames from the surveillance video to the 3-D model using unique, identifiable visual points seen in each. Once those two elements are matched together, it is possible to begin to make measurements.

One note: It’s critical for attorneys to reach out to a forensic expert as soon as possible in case the location changes in any way. If the city decides to do construction on the scene of the incident or plant some trees, for instance, that could impact the results. A simple repaving of the street can result in the loss of the traffic lines and cracks in the street that will prevent matching the laser scan to the original footage. Also, changes in weather, such as snow falling or tree foliage changed by seasons, could affect the creation of the model. It can take a few days to gather the information needed and up to a month to make a model and determine the answers to a client’s questions.

What Questions Can a 3-D Model Answer?

A 3-D model can reveal the critical information attorneys need to understand elements of their criminal or civil case, including the positions of cars prior to a crash, the speed and direction of vehicles, the height of a suspect, and precise distances between people and objects. 

When it comes to presenting the work to triers of fact in court, a fully active 3-D model can be displayed in the courtroom to show all angles of a scene. Still, images pre-chosen from the 3-D model can also be prepared ahead of time and shown to the jury. A forensic expert can prepare the best angles of the evidence so the most clear and simple demonstrative is shown during the trial.

Winning a Case With a 3-D Model

It’s apparent that the original surveillance footage – and even clarified versions of surveillance – isn’t always enough to rely on when it comes to cases. To determine what really occurred at the scene of a crime or civil incident, tap into the power of laser scans, 3-D modeling, and photogrammetry. This can be the exact information an attorney needs to gather facts that help prove their theory of a case in a court of law and come up with a win for their client.

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