FAAS AND NAA MAKE USE OF ONLY ONE CRITERION FOR THE PRESENCE OF GUNSHOT RESIDUES: THE CHEMICAL COMPOSITION OF THE ENTIRE SAMPLE TAKEN FROM THE FIRING HAND. SEM MAKES IT POSSIBLE TO ESTABLISH A FURTHER CRITERION: THE SHAPE AND APPEARANCE OF THE INDIVIDUAL PARTICLE. ONLY THOSE OBJECTS WHICH LOOK LIKE POTENTIAL GUNSHOT RESIDUES ARE ANALYZED. THE COMBINATION OF THESE CRITERIA INCREASES THE ACCURACY OF THE DETERMINATION. THIS ARTICLE EVALUATES THE SEM TECHNIQUE UNDER A VARIETY OF CIRCUMSTANCES AND WITH AN ASSORTMENT OF AMMUNITION. THE SEM TECHNIQUE WAS FOUND TO BE SUPERIOR TO OTHER TECHNIQUES, ESPECIALLY WHEN THE SAMPLES WERE COLLECTED A LONG PERIOD OF TIME AFTER THE ACTUAL SHOOTING....MSP