At a major crime scene such as a murder, detectives record measurements from every conceivable angle so they can attempt to explain scientifically how the crime unfolded.
But when it's time to present their findings to a jury, they often have to verbally explain what actually happened, aided only by two-dimensional photographs, which often do not cut it with juries that demand more visual presentations.
Some call it the "CSI effect," referring to the popular TV shows, but even animations won't always do the trick.
The problem, Berks County Detective Albert Schade III explained Wednesday, is that police and prosecutors have neither the time nor expertise nor financial resources in most cases to undertake expensive computer modeling.
Schade, a former Reading police officer and evidence technician who works in the forensic service unit of the district attorney's office, claims to have found a solution to this problem.
He discovered that he can use a computer program that can be downloaded for free online to create a detailed 3-D model of a crime scene from the measurements and drawings evidence technicians obtain from an actual scene. Then, with some modifications to gaming software, he can virtually take the viewer into the scene using a computer mouse.
This interactive, 3-D modeling is superior to regular animation, which, like a movie, doesn't give prosecutors the opportunity to change angles, zoom in, or do a flyover, for example.
"If I want to walk a jury through a crime scene I really can't do it with animation because they're all looking through one camera angle," Schade said. "Having an interactive way to walk through things and talk to people while doing it is very helpful."
Schade spent about two years working on his program for 3-D interactive modeling, which he demonstrated Wednesday to local media and the county commissioners at the county agricultural center in Bern Township, where the forensic unit is housed.
He collaborated with two other authors, Elissa St. Clair of the Naval Criminal Investigative Service, and Andy Maloney of FORident Software, on an article "An Introduction to Building 3D Crime Scene Models Using SketchUp," that was published Nov. 20 in the Journal of the Association for Crime Scene Reconstruction.
The purpose of the article was to introduce a relatively easy-to-use tool for modeling so investigators can create their own models without using expensive outside firms with no connection to the original crime scene.
The 3-D crime scene reconstruction tool already has been used to reconstruct two pending homicide cases and two resolved cases, which resulted in guilty pleas, said District Attorney John T. Adams.
It also may be used in fatal crash reconstructions in the future, he said.
Sgt. Robert F. Johnson, who heads the forensic services unit, said he knows of no other law enforcement agency in the state that has the in-house capability to create interactive 3-D crime scene reconstruction like his unit now does.
The 37 law enforcement agencies in Berks that are served by the forensic unit have entered a new world in crime-solving because of this harnessing of available technologies, Johnson said.
Thirty years ago, Johnson said, it was enough to present fact-based testimony to juries. Today, with the public seeing crimes solved with high-tech visual tools in fictional television shows, juries may feel something is missing if they're not presented with visual graphics, he said.
Copyright 2012 - Reading Eagle, Pa.
McClatchy-Tribune News Service