What does a fair trial look like in a country with no justice? Guatemala found out on October 3, when three judges concluded a month of hearings by finding Col. Juan Valencia Osorio guilty of planning and ordering the 1990 assassination of anthropologist Myrna Mack Chang. The verdict set a precedent: A senior Guatemalan military officer was convicted as the intellectual author of a human rights crime. And–another first–declassified US government records were used as legal evidence against Washington’s former allies.

Myrna Mack documented the fate of indigenous communities on the run from the army’s brutal counterinsurgency operations. Her work infuriated government and military officials. On September 11, 1990, army intelligence specialist Noel de Jesús Beteta stabbed her twenty-seven times as she left her office in downtown Guatemala City. She was left to die on the sidewalk.

Twelve years later, the trial of the men accused of planning the killing took place in a crowded courtroom in the capital, just blocks from the street where Myrna was murdered. Hundreds of spectators filled the folding chairs. Military families sat elbow to elbow with the country’s leading human rights activists–including Myrna’s sister, Helen Mack. Helen’s success in winning a conviction against Beteta in 1993 and her subsequent fight to bring his superiors to justice has made her a national champion.

Opposite Helen and her legal team sat the defendants–Gen. Edgar Godoy Gaitán, chief of the presidential staff in 1990; Valencia Osorio, head of Godoy’s clandestine intelligence unit, the Archivo; and Col. Juan Oliva Carrera, Valencia’s second-in-command and Beteta’s immediate superior. Six lawyers representing the officers jostled one another at a rickety table covered with papers, cell phones and laptops.

Simply to be in the courtroom was to make history. From the day Myrna was killed, Helen Mack and her allies have been relentlessly pressured by surveillance, harassment, death threats, physical attacks and murder. In 1991 the government’s chief homicide investigator was assassinated in Guatemala City. Key witnesses were silenced or forced to seek refuge outside the country. Judge Henry Monroy, who in 1999 ordered the trial to proceed against the three officers, resigned from the judiciary and fled Guatemala because of threats on his life. Even as the trial was under way, Mack’s lead lawyer, Roberto Romero, sent his wife and three children out of the country after a series of frightening incidents, including a drive-by shooting at their house.

Government stonewalling and a dysfunctional justice system also jeopardized the case. The defendants delayed the trial for years with dozens of frivolous appeals. The government refused to provide Mack’s lawyers with records necessary for their investigation, including basic information on the structure of the armed forces and biographical data on the three officers.

Faced with a conspiracy of silence, Helen Mack wove a web of circumstantial evidence. A newspaper vendor–whose testimony in 1992 helped convict Beteta–came out of hiding in Canada to describe the sophisticated surveillance he witnessed against Myrna’s home: the cars with darkened windows, the men with walkie-talkies. Civilian military experts explained how a national security doctrine imparted by the United States inculcated Guatemala’s army with an ideology strong enough to justify any means necessary to crush the left.

And US documents–released under the Freedom of Information Act from the secret archives of the CIA, the Pentagon and the State Department–identified the Mack assassination as a government-planned hit and described the army intelligence units behind it. In one cable sent by the US Embassy shortly after Myrna’s murder, then-Ambassador Thomas Stroock portrayed a government policy of “selective violence” and provided chilling detail on how the killings were covered up. “The sort of hit discussed here is carried out or directed by individuals who are members of the security forces, often military intelligence,” wrote Stroock. While the attacks were decided and organized at a “senior level…’Death squad’ personnel might often not appear on the official rosters of the security services and do not report for duty to official installations; they wait at home for orders, usually via the phone, or at times are picked up without prior notice to perform a job. They operate in cells so it is difficult to trace the orders up the hierarchy.”

These documents exist because of the intimate relationship between the United States and Guatemala from the start of the civil war in 1962 until it ended with the signing of peace accords in 1996. Despite US knowledge of the army’s role in nearly 200,000 civilian deaths, military and economic aid and covert intelligence support flowed almost uninterrupted for thirty years. All three of the officers accused of planning Mack’s assassination received training in US military schools.

The court accepted Helen’s argument that the crime was institutional, but singled out Valencia based on a taped interview with Beteta that identified him as the intellectual author. By convicting Valencia alone, the judges disappointed the prosecution but made an appeal by the colonel that much harder to win.

The courage of Helen Mack, her lawyers and the judges is cause for celebration in Guatemala and around the world, where efforts to prosecute the killers, kidnappers and torturers who once ruled so many nations continue. The Bush Administration has sought to politicize and obstruct the very idea of transnational justice. But this is what international justice is all about: putting murderers in jail. And the United States can play a crucial supporting role, wittingly or not.