In the late 1980s, the U.S. Department of Justice sought the forfeiture of funds that allegedly were derived from the sale of cocaine and then laundered and placed in domestic bank accounts. Throughout this litigation, the government Was confronted by claimants protesting the restraint of "their" money, which they had acquired through money exchanges in a "black" or "parallel" market transaction. The insidious use of the "black" or "parallel" markets by narco-traffickers in their attempt to successfully launder drug proceeds constitutes the greatest subterfuge in their efforts to evade the law. The "black" or "parallel" markets developed as an alternative means of exchanging local currencies for U.S. dollars in those countries that engage in restrictive currency exchange policies, most of which are in Latin America. Those involved with these markets have not only facilitated the deposit of so-called "flight capital" into financial institutions within the United States, but have also been proven to have aided and abetted the laundering of millions of narco-dollars.
Wilmer Parker III, Black/Parallel Markets: When is a Money Exchanger a Money Launderer?, 13 Penn St. Int'l L. Rev. 423 (1995).