Most trace evidence is harder to analyze. It must be sent to crime laboratories, where high-tech equipment can identify it. for example, a laboratory may analyze broken window glass from a crime scene. how does it bend light that shines into it? what chemicals is it made of? with a report from the lab, a CSI can search a computer database for car models that have the right kind of glass. Only a few models will match. the police may not have found the exact crime car,but they will know what kinds to look for.