Backspatter on the firearm and hand in experimental close-range gunshots to the head.

The deposition of backspatter on the firearm or person shooting can greatly assist the reconstruction of shooting incidents. Backspatter was investigated in experimental transverse gunshots (9-mm Luger) to the heads of calves (n = 9) from shooting distances of 0 to 10 cm. The firearms were examined with a magnifying glass; the surgical gloves and the right sleeve worn by the person shooting were examined with a stereomicroscope. On the firearms, backspatter of blood was found in five of the nine cases, and one or both gloves showed bloodspatter deposits in six and the right sleeves in four cases. Most droplets were 1 to 3 mm and circular or elongated. In addition, a fine spray of tiny blood deposits was present on the firearm and textiles in four cases. The distribution of the droplets on the firearms varied: the areas included regions shielded by prominent parts, and the droplets were predominantly located on the extensor side of the fingers and the radial aspect of the hands and sleeves. Backspatter of tiny bone fragments was recovered from the firearm and sleeve in only one case, but tissue (bone, fat, muscle, skin) was present on the ground in front of the entrance wound in seven cases. A careful investigation, including appropriate lightning and magnification, is necessary for reliable statements concerning the absence of backspatter or the extent of backspatter present.