Dan Testing News Today

>> a tool mark is a characteristic left behind during the process of using a tool to either cut, grind, file or polish a piece of metal. >> there can be hundreds of microscopic tool marks in a pipe used in a homemade gun. when ballistics experts compared the bullets from the victims to those fired from sedas zip gun, the tool marks were microscopically similar. finally police asked seda for a blood sample for dan testing. dna matched that of the letter from the zodiac killer. detectives had the ...