The 14-Year-Old Hit Man Tiny has always been just that. He's 14 years old and about four feet tall. His gray Levi's hang off him despite the belt he wears wrapped around his waist twice. He looks about 8, and no one would suspect him of inflicting harm. That's one of the reasons Tiny -- as his street name is translated -- makes an effective assassin. Colombia allows kids under 18 to kill without being held responsible. Tiny has carried out most of his hits with his best friend, El Raton, ''the mouse.''
