16 6 OTHER IMPRESSIONS Unit 16 Firearms Tool

16 -6 OTHER IMPRESSIONS Unit 16 - Firearms, Tool Marks, and Other Impressions

IMPERFECTIONS

IMPERFECTIONS • The presence of minute imperfections on tools imparts individuality to that tool.

FURTHER IMPERFECTIONS • The shape and pattern of such imperfections are further modified by damage and wear during the life of that tool.

FURTHER IMPERFECTIONS • The shape and pattern of such imperfections are further modified by damage and wear during the life of that tool.

COMPARISON MICROSCOPE • The comparison microscope is used to compare crime scene two marks with test impressions made with the suspect tool.

COMPARISON MICROSCOPE • The comparison microscope is used to compare crime scene two marks with test impressions made with the suspect tool.

TIRE TRACKS

TIRE TRACKS • Shoe and tire marks in pressed into soft earth a crime scene are best preserved by photography and casting.

ELECTROSTATIC LIFTING • The electrostatic lifting technique is particularly helpful and recovering barely visible dust prints on floor surfaces.

ELECTROSTATIC LIFTING • The electrostatic lifting technique is particularly helpful and recovering barely visible dust prints on floor surfaces.

ELECTROSTATIC LIFTING • The electrostatic lifting technique is particularly helpful and recovering barely visible dust prints on floor surfaces. • a sheet of mylar film is placed on dust mark.

ELECTROSTATIC LIFTING • The electrostatic lifting technique is particularly helpful and recovering barely visible dust prints on floor surfaces. • a sheet of mylar film is placed on dust mark. • film is pressed to mark using a roller

DUST IMPRESSION • A dust impression of a shoeprint on cardboard after chemical enhancement with Bromophenol Blue and exposure to water vapor.

DUST IMPRESSION • A dust impression of a shoeprint on cardboard after chemical enhancement with Bromophenol Blue and exposure to water vapor.

CHEMICAL ENHANCEMENT • Chemical enhancement can visualize latent or nearly invisible blood impressions In areas where a bloody foot where impression

CHEMICAL ENHANCEMENT • Chemical enhancement can visualize latent or nearly invisible blood impressions In areas where a bloody foot where impression

CHEMICAL ENHANCEMENT • Chemical enhancement can visualize latent or nearly invisible blood impressions In areas where a bloody foot where impression • very faint

CHEMICAL ENHANCEMENT • Chemical enhancement can visualize latent or nearly invisible blood impressions In areas where a bloody foot where impression • very faint • where the subject was track to blood

CHEMICAL ENHANCEMENT • Chemical enhancement can visualize latent or nearly invisible blood impressions In areas where a bloody foot where impression • very faint • where the subject was track to blood • leaving a trail of blood impressions