In February 1987, a special police force captured Carlos Lehder Rivas, a crucial figure in a drug trafficking organization that was estimated at the time to be supplying more than 80 percent of the world's cocaine. Within hours, Lehder was on a plane to Florida as a result of the extradition treaty between the United States and Colombia. However, within months the legality of this treaty was questioned. By June 26, 1987 the Colombian Supreme Court had ruled that the law ratifying the treaty was invalid. Thus, extradition is of limited value due not only to the limitations inherent in the treaties but also to the unwillingness of many governments to exercise the treaties. In fact, cocaine imports to the United States increased in the two years after Lehder's arrest. The Colombian extradition treaty was reactivated in 1989 after the assassination of a Colombian presidential candidate, but its future remains uncertain.