CNN Erin Burnett OutFront July 10, 2013 06:17:00
He uses what's called excelerometers. he used to use a tape measure, then lasers. now he creates a series of points at a scene, sometimes as many as 500, all in 3-d space. he says it's the most accurate reconstruction tool on the market. >> the laser follows me around. so it only takes one person to operate. >> reporter: in court, he told the judge how he created the model in this case and whether or not it matched the same conditions the night zimmerman killed martin. >> talk to me about the conditions, i assume it was filmed in the daytime. >> correct. >> i assume it wasn't raining. >> corre...