Drug Trade Feeds on Payoffs at Mexico Line
Special report, Bribery on the Border, finds corruption of law-enforcement officials, at local and Federal levels has become corrosive byproduct of vast river of narcotics that pours into US across 2,012-mile border with Mexico; at least 46 Federal, state and local law enforcement officials have been indicted on or convicted of drug-related corruption charges in last three years in border states of California, Arizona, New Mexico and Texas; number, which includes only cases in which drugs are transported across border by land, represents only small part of problem, since corruption often involves passively allowing smugglers to operate, making it extremely difficult to detect and even tougher to prosecute; Federal law enforcement officials openly concede they fear problem will grow worse as dealers have become more brazen and volume and value of drugs moving across border have skyrocketed; large-scale drug trafficking has continued, despite vows by successive US Administrations to stop it; traffickers, responding to US interdiction efforts in mid-1980's, shifted routes from Florida to Mexico, increasing reliance on Southwest border as transit point; Customs Service reports at five border crossings in California-Mexico border, marijuana seizures increased to 3,518 in 1996 from 2,490 in 1995--or more than 272,000 pounds of marijuana seized in 1996; photos; map; charts (L)