The instruments of law are here: courtrooms and trials, officers and jails, judges and prosecutors. Only justice is missing. When it comes to that inalienable American right, the people of this reservation are deprived. They can rely on neither the time-honored paternalistic order of the Sioux nor the safeguards of the U.S. Constitution.

Trudell Guerue, chief judge of the Rosebud tribe, learned that lesson three years ago.

On the afternoon of Oct. 21, 1981, Guerue was finishing work in the courthouse when he was presented a petition, signed by 231 people, seeking to postpone the next day's tribal elections. The petition claimed that council candidates had been buying votes in the hamlet of Ideal with cheap wine and food. Guerue, an Ivy League graduate and descendant of Spotted Tail, Rosebud's last traditional chief, realized that the issue was politically sensitive. The 33 tribal council members wield extraordinary power: They control the biennial elections, they distribute jobs and housing. And they oversee the tribal court. But the voting-irregularity charges had merit, Guerue concluded, so he ordered the elections temporarily postponed.

Councilman Matthew War Bonnet heard about Guerue's decision on the evening news and was enraged that a judge would intrude on the powerful council's turf. He picked up the phone and started calling other councilmen, seeking a new ruling, even a new judge. After a few calls, he had both. In the middle of the night War Bonnet issued a two-page edict that began: "Be it resolved . . . that Mr. Trudell Guerue Chief Judge is hereby suspended."

A new chief judge was appointed and reversed Guerue's order.

The next day, as voters headed to the polls, a frustrated Guerue went out and shot prairie dogs. He returned home that night to learn the full consequences of his assertion of judicial independence. The police authorities called with word that there was a warrant out for his arrest, signed by a tribal politician. The charge: using "technicalities to interfere, delay or block the election or cause confusion or the loss of confidence in the election system."

Several days later, police officers knocked on Guerue's front door and apologetically told him that he was under arrest. They frisked him, put him in the back of a squad car and drove him to the jail, where he was locked in a cell. He was joined there by one of the men who had first brought him the elections petition. He, too, had been arrested.

They spent the night talking and trying to sleep amid a raucous crowd of cellmates. Guerue remembers thinking, "Is this America?"

In terms of basic justice and civil rights, the answer is no.

In the rest of America, an election challenge could not result in arrest of the judge trying to resolve it. The independence of the judiciary, and its authority to interpret the law free from political interference, was established by the Supreme Court in 1803 in the landmark Marbury v. Madison decision written by Chief Justice John Marshall.

But such a vital constitutional question as separation of powers has never been resolved at Rosebud and most other reservations in the United States. Although the 755,000 Indians living on reservations are American citizens, they are not fully protected by the U.S. Constitution and the Bill of Rights. Federal courts, in decisions reaching back 150 years, have treated tribes as sovereign entities with broad powers to regulate themselves, justly or injustly.

In 1968, Congress passed the Indian Civil Rights Act, an effort to ensure civil liberties on reservations through a modified version of the Bill of Rights. But that act was rendered virtually meaningless a decade later by the Supreme Court, which ruled that it could be enforced only in tribal courts. The ruling was crafted by the court's liberals, whose intentions were to further the principle of Indian self-determination.

But the practical effect was to reduce freedom and concentrate power. It left the tribal court as the only potential check in the system. And as the Geurue case clearly shows, that court is subservient to and easily manipulated by the politicians in power.

"I'm very frightened," Guerue said. "I don't think the people understand how precarious our position is or understand the jeopardy we're in . . . . We can't provide a place where civil and human rights are adjudged fairly."

Guerue's concern was shared by Ronald Fisher who, as the highest ranking federal official here, reported in a memo to his superiors in the Bureau of Indian Affairs (BIA) on June 10, 1983, that the system of justice at the reservation had broken down. He wrote, "I am concerned that the residents of Rosebud are not being afforded due process and equal protection under the law." 'Worst of Both Worlds'

Last winter, this reporter spent eight weeks at Rosebud, interviewing scores of tribal members, judges, police officers, politicians, federal officials and other Indians who have come into contact with the reservation's system of justice. The investigation found serious violations of civil rights at every stage:

*As in the election challenge, the court is constantly pressured and coerced by the all-powerful legislative and executive branch -- the tribal council.

*Indigent Indians, unlike poor people in the rest of the country, are not guaranteed the right to legal counsel. That means virtually no one arrested on this impoverished reservation has an attorney, placing in grave doubt the fairness of court proceedings. Of the approximately 5,000 Indians prosecuted here each year, only a handful have been defended by lawyers.

*Lawyers are hard to come by at Rosebud in any case. There are four legal services attorneys, but as a policy they have not handled criminal defense work in the tribal court. The tribal judges are not fully trained lawyers. Of the four now serving at Rosebud, one spent a year at law school and the others have paralegal training. The prosecutor is a college student.

*The Rosebud police force, staffed by Indians and run by the federal government, illegally has detained hundreds of Rosebud Indians without due process. Many arrested on minor charges have been held as long as a week in jail without receiving a court hearing.

*Reservation Indians have the constitutional right to file writs of habeas corpus with the federal courts to determine if they have been detained unlawfully, but that process is almost never used here. Tribal court officials said they are too overworked to help defendants file such petitions, and many who might be eligible apparently are not aware that such a right exists.

*Rosebud's citizens in theory are guaranteed speedy trials, but in practice do not get them. Records show 650 cases in the tribal court where Indian defendants were charged with crimes and never given a trial. The case files, some as old as four years, are gathering dust in three large cardboard boxes in the back of the courthouse.

The lack of legal justice is less visible, more subtle, than most of Rosebud's other problems -- unemployment, poverty, poor health care, alcoholism. Yet it pervades almost every aspect of daily life here, breeding cynicism and despair.

Some blame the civil rights problems on a lack of funding and trained personnel, but there is also a major philosophical question of how justice should be dispensed -- whether it should be patterned after the U.S. Constitution with a separation of powers, or more closely resemble the ancient way, when Sioux tribes moved across the plains as large families and were ruled by groups of elders whose decisions were respected as the only law.

A few tribes have resisted westernizing their justice systems. The Pueblo in New Mexico use tribal governors as judges and have no written laws or court procedures. But more than 100 reservations have attempted to fashion justice systems similar to those in any city or county, with varying degrees of independence and sophistication. The Navajos, for instance, have six district courts, judges with lifetime tenure, an appellate system, a bar association and a full-fledged justice department.

Rosebud, in trying to make the transition from ancient to modern, has been caught in a legal no man's land.

"Our judicial system is patterned after a system that's so foreign to us, our culture, our values, that we're struggling in two worlds, trying to find the medium, the balance," said Rosebud Judge Larry Salway. "And it's difficult. I believe it's the worst of both worlds." Politics of the Court

Salway, 38, a former meatcutter and teacher who presides over juvenile cases, looked up from his desk, shaking his head. He had just received his second phone call of the day from a high-ranking tribal official who was trying to influence his decision in a child custody case.

"See all my gray hair? Six months of it," Salway said. "They come up here and try to put the pressure on me . . . . I get it all the time. Different people, agencies, and they pressure me . . . . They want me to make a decision in their favor."

Salway once kept a running account on a yellow legal pad of every attempt to influence him, but he finally gave up. "I had two, three, four, five of those pads all filled. I was spending time writing down what everybody said, and controversial things, and I thought: 'Forget it. Either people are going to trust me the entire year or they can remove me as a judge.' "

After work, Salway said, he often takes walks in the woods to relieve his anger at the tribal politicians. "Sometimes I'll scream at the trees out here and just tell them what I think of them. They can't fire me. They can't talk back."

The power of tribal council members is such that at times they have simply rewritten the laws to avoid court decisions against them. In February 1982, a car dealer in the town of Winner, S.D., which borders the reservation, filed an impoundment order in tribal court against an influential tribal council member who allegedly had not kept up payments on a 1979 pickup truck.

According to Lorraine Walking Bull, then the court clerk, the half-ton truck was seized by tribal police, but before a court hearing could be held, the council member convened a backroom session of his colleagues. They drew up papers declaring that certain cases, "such as impoundments," could no longer be heard in the tribal court.

"They had some fancy language for it," Walking Bull recalled. "I felt that the decision should have been a judge's, and it should have been held in an open courtroom . . . . It was all done by judiciary committee members playing judges."

This breakdown in the order of justice has extended to the practices of some judges. Tribal Prosecutor Charles Elk Looks Back said he was trying a case last Nov. 29 before Judge Spencer Bear Heels involving a man who was accused of involvement in the fire-bombing of a house in St. Francis. Before the trial, the defendant got a private meeting with Bear Heels and emerged boasting that the judge said he would find him innocent. The trial was held, and Judge Bear Heels delivered a verdict of not guilty.

The judge who has had the most problems with the tribal council is Guerue, who remained suspended for five months and was nearly impeached after his controversial election decision in 1981.

Peter Gregory, a Sioux Falls attorney who knows Guerue, said he believes Guerue's unpopularity with the Rosebud council stems from the perception that "somehow he's too tainted with the white man's education, words and beliefs, and that that jeopardizes his Indianness.

"And I think the truth about him is that he sees what must be done if we're ever to resolve this," Gregory said of Guerue. "He was raised as an Indian and he has a tremendous amount of pride in Indians . . . . He wants Indians to reemerge like a phoenix from the ashes -- economically, politically, judicially -- and he places a great deal of importance on that reemergence, and the protection of the individual, and the establishment of the court system."

Guerue, 37, lived away from the reservation for nearly 16 years, with the Army in Vietnam, at prep school and Dartmouth College in New England, and a year of law school in Indiana. Before he returned, he said, his friends had warned, "Don't go back there. There's nothing for you." But Guerue remembered thinking, "As long as you don't come back, there never will be anything."

He was influenced by what he had learned off the reservation, such as the decision in Marbury v. Madison that said it was "emphatically the province and duty of the judicial department to say what the law was." At Rosebud, Guerue felt, he, not the tribal council, must be the "judicial department."

"I'm considered a threat because I'm quite willing to tell these people that I think the law comes before all of us," he said.

After his controversial ruling, the council accused him of threatening "the political integrity of the tribe." Councilman Seth Big Crow called him "the most dangerous one up there." War Bonnet, the councilman who suspended Guerue, explained, "On this reservation, there are 33 gods sitting around a council table, and that's the truth. What they say goes." He likened the tribe to a developing nation that had lost much of its land, religion and cultural identity. The tribe needed to consolidate what powers it had left, and Guerue was seen as trying to diminish them. Of the decision to suspend him, War Bonnet said, "I'd do it again if I had to."

Rosebud's troubles in this area are not unique. "On reservations nationwide, if a judge does something which the tribal council doesn't like they can roll his head and get a new judge who will do it the way they want it," said Larry Long, Rosebud's former legal counsel.

The most recent example was at the Cheyenne River reservation about 200 miles north of Rosebud. In 1982, the Cheyenne council ignored a vote by a majority of Indians there to redistrict the reservation's election districts. When Chief Judge Gilbert LeBeau directed the council to adhere to the voters' mandate, the council fired him.

Within days a new judge -- the father of the chairman -- was appointed, and immediately issued a new ruling in the council's favor.

The challengers then asked a federal judge in Pierre for help. He could do nothing, bound by the 1978 Supreme Court ruling that tribal disputes were to be heard only in tribal courts. The BIA refused to get involved. As a last resort, LeBeau and some of the challengers ran for council seats. They won the primary this June, but on July 12 the council took the ultimate act of stifling dissent: it "forever barred" LeBeau and the other challengers from holding appointed or elective office on the reservation.

"There is no justice," said LeBeau, a World War II Navy veteran. "The federal courts say we're not entitled to the Constitution of the United States . . . . We fought for that Constitution, and yet we're denied the rights."

"It looks bad. It is bad. I mean it sounds like Nicaragua or El Salvador," said the challengers' attorney, Terry Pechota, a Rosebud Indian who practices law in Rapid City, S.D., and served as U.S. attorney for South Dakota during the Carter administration. Lack of Representation

The Sixth Amendment to the Constitution says that all Americans are entitled to defense counsel, and in 1963 the Supreme Court ruled in the case of Gideon v. Wainwright that lawyers must be provided for defendants who cannot afford to hire them. But neither the Sixth Amendment nor the celebrated Gideon ruling apply in the reservation court. The Indian Civil Rights Act offers attorneys only at a defendant's expense. The results have been devastating at Rosebud.

"A lot of times they get convicted whether they are guilty or not," said Tribal Judge Bear Heels, who presides over criminal cases in the Rosebud court. "They have no chance . . . . There's nothing I can do. The odds are against them. I can't be their attorney."

Many defendants stand mute, or agree to plead guilty, even if they are innocent, because it is the simplest thing to do.

"I felt all alone sitting there," said Lavina White Horse, 40, a Soldier Creek woman charged with disorderly conduct late last year. She felt she was innocent, that what the police called disorderly conduct was simply a quarrel with her husband. But she was intimidated by the court, she said, and had no idea how to mount a legal defense. At one point the officer who had arrested her whispered, "Why don't you just plead guilty and get it over with?" And so she did, recalling, "I knew how to plead guilty."

Tribes have the authority to prosecute Indians who commit crimes on reservations except for defendants charged with murder and 13 other specified felonies, which are handled in federal court. Tribal judges may impose sentences of up to six months and fines of $500, a small fortune here.

Melvyn Running Horse, a paralegal, assists in about one-third of the cases and is generally effective, but on days that he does not appear there is no one to advise defendants. Running Horse said he has no time to file habeas corpus petitions for prisoners -- requests that a federal judge release an Indian who is being illegally detained.

"The bottom line," said Guerue, "is that a lot of people receive jail sentences and fines and don't get the representation that any American would get in any court system."

For those few defendants who can afford to hire attorneys, there is a sure-fire way to manipulate the system. Stan Whiting, a Rosebud Indian who practices law in the town of Winner, said he advises clients to plead not guilty and ask for jury trials. "That's all you have to do," Whiting said. "They just never have trials . . . . Just dies on the vine." Illegal Detentions

On the afternoon of Dec. 22, 1982, Lloyd Little Bald Eagle, 55, a ranch hand, was walking in Parmelee between the post office and Betty Red Owl's general store when two police officers picked him up on a charge of public intoxication. The police held him in jail five days before he was released.

That day four other men -- Nelson Iron Shell Sr., Nelson Iron Shell Jr., Matthew Stewart and Raymond Hollow Horn Bear -- also were released from jail. Records show that all four had been held at least five days before they were taken to court for a hearing.

The Rosebud legal code requires that police file formal charges on all prisoners and that they be brought before a judge within 48 hours. But the code has rarely been followed. The police department, known as the Branch of Law and Order, has for years picked up Indians on minor offenses, then held them for up to a week without charges or hearings.

"It's all illegal detentions," said Betty Laverdure, a federal judicial specialist who supervised the Rosebud Court for the BIA from 1977-83. "They're so used to arresting people that they don't file the formal complaints."

Chief Judge Guerue first brought the matter to the BIA's attention in a letter dated May 16, 1983, charging that Rosebud police were "engaging in the illegal and unconstitutional practice of arresting people, then not charging and prosecuting through the Rosebud Sioux Tribal Court." Guerue concluded, "This type of police state action by a police department must not be allowed."

Laverdure investigated and counted about 200 cases a year through 1982 in which Indians were held by police illegally. There have been fewer in recent months, according to Guerue.

Officer Ronald Eagleman, on the tribal police force since 1969, said of the practice: "Back in the '70s . . . it was really bad. People would get arrested, brought into the police department , held for two days and then released without a complaint filed on them. We should have had a lot of lawsuits then. We were pretty lucky . . . . I reported it time after time, but there was no discipline taken. It went on and on."

"I guess you can say it's sloppiness, just about anything," said Gerald Gunhammer, the senior police investigator. "A police officer brings somebody in, throws him back there, and things get a little busy and he forgets to file the proper report. Or, you do file the proper reports and they disappear. Somebody forgets somebody is back there, and he sits back there a week without knowing what he's in there for."

March 10: Rosebud Jail. The cells are crowded. Moses Left Hand Bull, Peter Four Horns, Alvin Eagle Feather -- public intoxication. Clement Standing Elk -- walking drunk on the highway. Robert Runs Above -- disorderly conduct. Mike Black Spotted Horse -- escape. Harriett at the Straight -- assault. No mattresses, or chairs, just people shivering on the cement floor. Old copies of the National Enquirer, clogged toilets, shoes without laces. Prisoners try to kill themselves regularly here with whatever they can find. In 1983, they used knives, razors, tobacco can lids, shoelaces, shirts, broken light bulbs, pants, socks.

Lenis Bear Flying Over Water is in Cell 5. Like many in the Rosebud jail, he was picked up on a minor complaint -- disturbing the peace at his girlfriend's mother's house in Soldier Creek. The charges soon multiplied out of control: two counts of disorderly conduct as he was being booked, two escape charges after a jail guard harassed him.

He had sent a note to the court, begging for his freedom because he could not pay his fine. A judge let him out, but he was arrested the next day, found walking drunk down Highway 18. More fines, totaling $397. He attempted to commit suicide by slashing his left wrist, but a guard saved him. "My mind was on that big fine," he said later.

By July 25, after more escape attempts, the fines totaled $679. The judge agreed to free him for a promise to pay $100 each month until February 1985. Bear Flying Over Water promised, but he could not comply. Ten days ago, a warrant was issued for his arrest. The last time Prosecutor Charles Elk Looks Back saw Bear Flying Over Water, they had an exchange that captured the frustrations of justice at Rosebud.

"I just told him that I was glad he was getting out," Elk Looks Back recalled, "but that it would be pretty much inevitable that he would be back. He kind of looked at me like he knew I was right."