Personal body armor, as developed originally, was inappropriate for normal police work because of weight and awkwardness. By 1975, however, dozens of manufacturers were producing soft, lightweight body armor products designed to stop most types of bullets, but penetrable by particular types of rounds. It is feared that knowledge of this susceptibility will encourage criminals to use more dangerous classes of ammunition and will lead to a fatalistic attitude among police officers. Factors determining the bullet's penetration capability are surface area of distribution and velocity. After careful study, the DOJ determined it cannot justify legislation banning all ammunition capable of penetrating soft body armor worn by law enforcement officials. Nevertheless, it developed a stopgap proposal establishing a minimum, mandatory prison sentence of 5 years for the use of armor-piercing handgun ammunition during the course of a Federal crime of violence. The sentence would be imposed only when it can be proven that the ammunition would penetrate the Type 11A body armor.