The demand for law enforcement to have access to less lethal tools has never been higher. Within the last ten years, products from TASER® International have dominated the marketplace and are now in use in more than 16,000 police agencies worldwide. As investigators, scientists, and crime scene analysts, Electronic Control Devices (ECD) such as TASERs will be encountered in casework. Their role, capabilities, and limitations must be understood to properly collect and analyze the evidence involved. These devices and their components can be analyzed to determine proper function, establish a hit or a miss, and in some cases determine the duration of shock to assist in the reconstruction of a field “failure” or in custody death.