DRUG trafficking has become a serious problem in Brazil in the last five years, but its reach has for the first time extended to the national Congress.The July arrest of a federal deputy's brothers - caught allegedly with half a ton of cocaine - and unproven suggestions that the deputy himself was involved, have brought home to many Brazilians how widespread the drug trade has become in Rondonia, an Amazon state that has an 840 mile border with Bolivia. The deputy, Jabes Rabelo, represents this thinly-populated western state that stretches 540 miles across, boasting only one paved highway. In Rondonia, the cocaine business mixes with gold mining and illegal woodcutting. "Lots of people come from far away to this region and suddenly, they are doing relatively well, financially," says Sonia Maria Angelim, director of the local federal police bureau in Guajara Mirim, Rondonia, a small town that straddles the border formed by the Mamore river. The town of 20,000 residents is full of splendid homes, late-model cars, and, unlike many towns in the Brazilian hinterland, paved streets. In a phone interview, Ms. Angelim tells of how traffickers come to Guajara Mirim with cars stolen in southern Brazil, and sell them across the border in Bolivia for cocaine. In July, the townspeople protested when police arrested a respected local pharmacist because he had three tons of chemicals in storage. "It was more chemicals than this city could consume," the policewoman says. "We deduced it would be sold to Bolivians for [cocaine] refining." So far, there is no direct evidence Deputy Rabelo was involved with his brothers' purported cocaine trade, although many Brazilians assume so. One brother was carrying a fake congressional identification card when arrested, and investigators are trying to determine if Rabelo issued it, giving his brother the privileges of a congressional aide. Congressmen enjoy the privilege of parliamentary immunity from prosecution. But Rabelo's immunity has been revoked so he could be prosecuted for receiving a stolen car, a crime for which police say they have the evidence. "In the last 40 years, Congress has never given [the judiciary] permission to prosecute a deputy," says federal Deputy Jose Elias Murad, who heads a congressional committee to investigate drug trafficking. "This is a sign that things are changing." The congressional investigation, which included a two-day trip to Rondonia, was shocked to find that one mayor there had built a 40-mile road to the Bolivian border, dubbed "Trans-coca." "Ten years ago, Rondonia had a population of 450,000," says Deputy Murad. "Today, it's 2.5 million. It's the far West ... like in the last century in the United States." According to press reports, cooperation between the United States Drug Enforcement Administration (DEA) and Brazilian government is increasing, with the US willing to spend more money in Brazil. Brazilian police say information from Rabelo's brothers led to a huge cocaine bust in New York Aug. 15, the first time Brazil's federal police have helped the DEA catch traffickers in the US. At home, federal police last month began a crackdown in Rondonia, fearing the region is becoming an extension for Colombian drug cartels. So far the crackdown has consisted mostly of roadblocks. Alberto Laserre, the federal police superintendent for Rondonia, said in a phone interview that the crime rate has dropped to near zero, while local cocaine prices have risen. "We are showing that the federal government is present in the state, because the complaint [used to be] that it was too distant," he said. A problem, however, is that police surveillance has diverted drug trafficking to border areas. "The big fish don't come through here, they won't risk their skins," Angelim says of drug arrests in Guajara Mirim. "They take another route, an air route." The news from Rondonia has also led politicians in the capital of Brasilia to take a new look at themselves. "The national Congress is the face of the country so it has all types of individuals," Murad says. "We must have the strength to show that a man in the public eye is an open book, like in the US ... that Congress is a dangerous place for [those who do wrong]."