>> but if david duyst shot his wife two times at close range, why was there no blood spatter on his shirt? >> when the clothing was sent over, it was labeled as a suicide, not a homicide investigation. they just basically held it up and looked at it with a naked eye. >> the clothing was examined again. this time, criminalists used a high-powered microscope connected to a video camera. under high magnification, there were stains invisible to the naked eye. tiny microscopic blood stains. >> these stains were referred to as back -- they're coming from the entry wound and they're ejected back towards the shooter. >> the blood penetrated into the fabric weave. the signature sign of high velocity blood spatter. and there was high velocity blood spatter on the back sleeve