For more than two hours on the night of May 16, 2007, Shane Maggi terrorized a Native American couple at their home on the Blackfeet Indian Reservation in Montana, pistol whipping them and firing bullets above the husband's head.

Maggi, who suspected the couple had stolen his drugs, was convicted by a federal jury in 2008 and sentenced to more than 42 years in prison. But an appellate court here found Maggi did not meet its definition of a Native American and, as a result, had been prosecuted under the wrong federal statute.

The 9th U.S. Circuit Court of Appeals overturned Maggi's conviction in March.

The case illustrates a hazard of the complex legal system used to mete out justice on American Indian reservations — a system that relies largely on race to determine jurisdiction, and then charges police and prosecutors with the sometimes delicate task of determining a person's race.

"The whole flaw in the system is that it's premised upon being an Indian defendant or Indian victim, and yet we have no clear-cut definition of who an Indian is," said BJ Jones, director of the Tribal Judicial Institute at The University of North Dakota law school.

In most states, federal and tribal authorities can arrest and prosecute Indians on Indian lands. But criminal offenses by non-Indians are handled by federal or state authorities, depending on whether the victim is Indian.

That means when a crime is committed on Indian lands, authorities must determine the suspect and victim's race before they can answer fundamental questions like which agency can make the arrest and try the case, and sometimes which law applies.

Tribal officials and legal experts say this process creates confusion that can lead to delayed cases and even overturned convictions on reservations, which already endure high crime rates and shortages of law officers.

"Everybody in law enforcement wants to do the right thing," said Sen. Byron Dorgan, D-N.D., chairman of the Senate Indian Affairs Committee. "It's just, you have this very complex, Byzantine jurisdictional system that impedes effective law enforcement."

Legislation introduced by Dorgan and signed into law in July aims to increase the powers of those tribal police who are unable to arrest non-Indians on their reservations.

Tribal officials say enrollment cards generally make it clear who is a tribal member, but difficulties can arise when that identification is lacking. Matters also can be complicated by intermarriage with other races and the movement of Indians to other tribes' reservations.

"We've had people claim to be Native that weren't and people say they weren't Native that were," said Mike Lasnier, chief of police for The Suquamish Tribe near Seattle, Wash.

It's not clear how many cases similar to Maggi's have come through the courts. The 9th Circuit has overturned at least three others in the past several years on grounds the defendant's Indian status at trial was incorrect. The issue has surfaced in still two other cases before the 8th U.S. Circuit Court of Appeals in St. Louis, Mo.

"It seems to me the question is coming up increasingly," said 9th Circuit Judge William Canby, an Indian law expert. "It's become a cumbersome system."

Congress has not established a universal definition for who is an Indian, and tribes have varying requirements for who constitutes a member.

Courts have generally held that a person is Native American if he or she has Indian blood and is enrolled in a federally recognized tribe. But other factors can come into play.

In the 8th Circuit cases, both involving assault, the court found that although the defendants were not enrolled in a tribe, they were Indian because they had Indian blood, held themselves out as Indians and lived on a reservation. Their convictions were affirmed.

In Maggi's case, however, the 9th Circuit rejected a similar set of circumstances and concluded he was not Indian because he was not enrolled in the tribe.

"The most basic issue in any kind of legal proceeding is jurisdiction," said Troy Eid, former U.S. attorney for Colorado. "If you don't know jurisdiction at the outset, the parties who prosecute can be totally different."

Eid recalled a 2006 case on the Southern Ute Indian reservation in Colorado where a non-Indian driver allegedly high on marijuana slammed head-on into another vehicle, killing an elderly woman and her 8-year-old granddaughter.

The federal government, rather than tribal or state authorities, has jurisdiction over crimes committed by non-Indians against Indians on reservations.

But prosecuting this case presented difficulties.

Although the elderly woman was clearly Indian, it took months of study by the tribal council to determine the girl was not Indian, Eid said.

That meant state, rather than federal, authorities had to handle prosecution for the girl's death.

In the end, the driver wound up in different courts for different victims in the same crash.

In federal court, he was sentenced to 3½ years in prison for involuntary manslaughter in the grandmother's death. In state court, he received three more years after pleading guilty to criminal negligence and other charges in the 8-year-old's death.

Dorgan's bill aims to make it easier for tribal officers to satisfy the training standards needed to obtain federal arresting power. One provision calls for training sessions to be conducted on reservations as opposed to several federal offices around the nation.

"We do have a crisis on many of these reservations of violent crime," Dorgan said. "And we need to address it."