By JUAN FORERO
LA LOMA, Colombia — In March 2001, during what union members describe as a labor dispute, two union leaders were pulled off a company bus after it left the coal mining compound here and were shot dead by paramilitary gunmen. Six months later another union leader was also assassinated.
For Colombia, such killings are routine; nearly 90 percent of union leaders reported killed worldwide die here. Few of the murders are ever resolved.