Since early last year, the National Congress has wrestled with a crime spree--alleged sterilization campaigns, death squads, murder-for-hire, deadly developers.

Yet the lawlessness didn't come from urban thugs or rural outlaws. The crimes allegedly were committed by members of Congress.

In the latest case, the legislature last month expelled Hildebrando Pascoal, a member of its lower house, the Chamber of Deputies, for a lengthy list of malfeasance--heading a death squad in his home state in western Brazil; trafficking drugs; taking payments to allow prisoners to go free. He's also accused of overseeing one killing in which a man was dismembered with a chain saw.

The cases have cemented public cynicism toward Brazilian politicians at a time when Congress needs all the support it can get to push through important fiscal reforms.

They also have forced a debate over whether Brazilian law should continue to shield members of Congress, who cannot be tried for any crimes they are alleged to have committed before being elected.

Even when Congress expels a member, allowing the courts to try him or her, the member's influence may still help the legislator to evade justice, or at least to delay it. Expulsion didn't matter in the case of developer Sergio Naya, who was ordered to pay six people who lost their apartments in a building collapse in Rio de Janeiro that killed eight people.

Naya, who likely will face trial in Brazilian federal court, left the country after his expulsion. Today he's building hotels in Florida.

"It's a kind of official permit for illegal activities," says political consultant Jose Luciano Dias, referring to the law that protects Congress members. "If you get elected, it's very difficult to sue you or put you in jail."

Dias said the recent cases "contribute to the worsening of the image of Congress. The public just thinks, 'one more corrupt politician.' It reinforces an old, ingrained view of Congress."

The timing could not have been worse. Investors are looking to Congress to push through critical fiscal reforms--including an overhaul of the tax system and significant cuts in social security expenses. But their hopes wither with each new scandal, as an increasingly bitter public digs in its heels.

Brazil's electorate has long held Congress in low esteem. Corrupt politicians, especially those from rural areas, often slide into office because they make lavish promises to their mostly poor constituencies and are prosperous enough to buy votes. Pascoal, for example, is accused of trading cocaine for votes.

The Chamber of Deputies is an especially unwieldy place, where members often skip crucial votes. For years there was a problem with nonmembers voting as representatives. Now, votes are verified with fingerprints. And for years, deputies have changed parties, says one Brasilia-based political analyst, as often "as they change their underwear."

Those sorts of problems symbolize a larger one with Brazilian politics, say analysts and members of Congress. Too many politicians run "to serve themselves, or small economic groups," said Nilmario Miranda, director of the chamber's Human Rights Commission. "They're not running to represent the country."

Brazilian law facilitates those "adventurers," say Miranda and political analysts, because it protects members of Congress from prosecution, unless colleagues expel them. And only recently has Congress been willing to boot tainted members.

Even when Congress members do send away colleagues, they often must do so on lesser charges or technicalities. Congress expelled Pascoal not because he was accused of murder and drug trafficking, but because he insisted that it was common practice among members to sign permits allowing prisoners to go free. He thus was accused of violating congressional decorum.

And Naya lost his mandate because he signed a governor's name to critical documents associated with the construction of some of his buildings.

The cases of Pascoal and Naya are only the most notorious in a rash of recent congressional wrongdoing.

One member, deputy Talvane Albuquerque, is in jail, accused of hiring a hit man to kill a congresswoman in December 1998 because he wanted to take her place in the lower house. He had been runner-up in the election that she won.

Another deputy, Roland Lavigne, of the northeast state of Bahia, is accused of forcing Indian women in his state to be sterilized as part of a campaign to make the Pataxo Ha-Ha-Hae indigenous group extinct. Landowners allegedly wanted to take over an area that the group inhabited.

All of these congressmen have denied wrongdoing. Pascoal's attorney said that his client considers himself "a victim of diabolic conspiracies that not even [late novelist] Mario Puzo would be able to imagine."

Nilo Batista, one of Naya's attorneys, says that the former legislator isn't responsible for what happened to the building. "The construction was perfect," Batista said. "The building didn't fall because of bad materials. There were no defects in the construction."

Analysts believe that Congress could avoid such cases if Brazil's judicial system moved faster. Sometimes congressional candidates have had repeated jousts with the law. But if they can delay judgment until after they win a seat in the legislature, they're safe for as long as they stay in office.

Pascoal's alleged crimes go back more than a decade. Yet the wealthy, well-connected resident of Acre, in western Brazil, repeatedly avoided prosecution. During the 1980s, one murder trial ended in acquittal; in another episode, prosecutors dropped a murder case in which he was a suspect.

"These kinds of cases wouldn't happen with a more efficient justice system," Dias said. Referring to Pascoal, he said, "It can take years to prosecute a guy like that."

Some members of Congress take heart from the institution's recent enthusiasm for self-policing. For years, they refused to expel colleagues. Since 1995, however, several members have lost their mandates.

Severino Calvacanti, a veteran congressman in charge of investigating colleagues accused of wrongdoing, says "we're tougher now," and defends the legislature. "There's corruption in congresses all over the world," he said. "It's not unique to Brazil."

Such statements fail to comfort Brazilians such as Barbara Martins, 43, who lost her ex-husband and her 12-year-old daughter in the February 1998 collapse of Naya's 22-floor Palace II apartment building.

She sits surrounded by a dozen or so former apartment residents. One lawyer, whose office was in the complex, says she lost her business. A physician says the trauma of losing his residence and most of his belongings contributed to the meltdown of his marriage. A mother says that her then-8-year-old son suffered psychological troubles. He didn't talk for two days, then took to building little towers and destroying them as he shouted, "The building's falling, the building's falling!"

After the Palace II crumpled, investigators said that they believe materials used in its construction might have included sea shells. Today Naya has built a hotel, started before the fall of the Palace II, in Orlando, Fla. Earlier this year, Martins and others went to Orlando to protest in front of the Sandy Lake Towers.