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Case Information: Myrna Elizabeth Mack Chang
Myrna Mack
DATE OF BIRTH:October 24, 1949

Summary and Current Status

Guatemalan anthropologist Myrna Elizabeth Mack Chang was murdered on September 11, 1990, in Guatemala City in what is widely believed to have been a politically-motivated killing. At the time of her death, she had been researching and publishing information about the plight of internally displaced persons in Guatemala.

In 1993, a low-level sergeant named Noel de Jesús Beteta Álvarez was convicted of the murder and sentenced to 25 years in prison for the crime. This was a historic ruling because it was the first conviction of anyone from within Guatemala’s security forces for one of the thousands of brutal murders that occurred during the 36-year internal armed conflict in that country.

Three years later, three high-level military officers were indicted for ordering the murder and, after multiple delays, were subsequently put on trial in September 2002. In response to a request by Myrna Mack's sister, Helen Mack, the CHR sent two of its members (Morton Panish, NAS/NAE; and Mary Jane West-Eberhard, NAS) to attend the second week of the trial of the three officers and to meet with scientific colleagues who have been threatened as a result of their efforts to advance the case through the Guatemalan judicial system. The CHR issued a report on the mission, entitled Guatemala: Human Rights and the Myrna Mack Case.

On October 3, 2002, a three-judge panel convicted and sentenced one of the officers—Colonel Juan Valencia Osorio—to 30 years in prison and acquitted the other two—General Edgar Augusto Godoy Gaitán (Col. Valencia’s superior officer) and Colonel Juan Guillermo Oliva Carrera (Col. Valencia’s deputy)—on the grounds that there was insufficient evidence that they were directly involved in ordering the murder. Upon appeal, on May 7, 2003, the Guatemalan Fourth Appeals Court overturned the verdict against Col. Valencia and upheld the acquittals of the other two defendants. The prosecution then appealed the Appeals Court’s decision to the Guatemalan Supreme Court. On January 20, 2004, the Supreme Court ruled to uphold the conviction of Col. Valencia as an “intellectual author” of the assassination of Myrna Mack and to confirm his 30-year prison sentence. Regrettably, this did not happen because Col. Valencia eluded authorities and went into hiding. He remains a free man.

The case was also vigorously pursued through the Inter-American system. In February 2003 the Inter-American Court on Human Rights heard oral arguments in the case brought by the Mack family against the Guatemalan government for allegedly failing to ensure timely justice in the Mack case. On December 19, 2003, the Inter-American Court unanimously ruled in favor of the Mack family. The Mack case is widely viewed as a test case for the rule of law in Guatemala. There were numerous death threats made against witnesses, judges, and others involved in the case, and several were forced into exile. Dilatory tactics plagued the proceedings. The success in moving the Mack case through the Guatemalan courts and the Inter-American system can be primarily attributed to the hard work, persistence, and courage of Helen Mack.


The Committee on Human Rights (CHR) has worked on Myrna Mack's case since shortly after her brutal murder on September 11, 1990. (Ms. Mack was stabbed to death in Guatemala City outside of her office.) She was one of the founders of the Association for the Advancement of the Social Sciences (AVANCSO) in Guatemala and dedicated herself to conducting research and writing scientific reports on the impact of insurgency and counterinsurgency activities on impoverished Mayan communities in Guatemala. Some apparently viewed her work as a threat to Guatemala’s national security, and it is widely believed that military intelligence officials ordered her killed.

Myrna Mack's sister, Helen Mack, has been instrumental from the outset in pushing the case forward through the lengthy and complicated Guatemalan judicial process. In 1993 a low-level sergeant of the Presidential General Staff (EMP, Estado Mayor Presidencial)—Noél de Jesús Beteta Álvarez—was convicted of the murder and sent to prison. In retaliation, however, Helen Mack and her family, as well as AVANCSO staff members, suffered harassment, including numerous death threats believed to come from the military. The homicide detective who initially investigated the case and wrote a report implicating members of the military was murdered. Most of the judges, lawyers, and witnesses involved with the case received numerous death threats. Several judges in succession withdrew from the case, and all of the witnesses fled the country in fear for their lives. Criminal proceedings took over three years, and the case was overseen by twelve consecutive judges before a verdict was reached.

In 1996, three high-level military officers were arrested and indicted for their alleged roles in ordering Myrna Mack's murder. They are former EMP head General (r) Edgar Augusto Godoy Gaitán and Colonels Juan Valencia Osorio and Juan Guillermo Oliva Carrera. Shortly thereafter, however, military leaders, were successful in gaining their release from prison pending trial

In January 1997, seven months after they were indicted, the three filed a petition requesting amnesty under the Law of National Reconciliation, passed just the week before. The law calls for "the extinction of criminal responsibility" for political and related crimes committed during the armed conflict. The court ruled, however, that because there was no rational relation between the crime committed and political aims related to the war, the officers were not eligible for amnesty. Two appeals of that decision brought by the defendants were dismissed on technical grounds.

On January 25, 1999, just three days before a scheduled hearing in the case of the three former military officers, and in response to requests by Helen Mack, the CHR, and others, the U.S. government declassified previously secret documents—including diplomatic cables and CIA reports—relevant to Myrna Mack's murder. At the hearing, on January 28, 1999, Judge Henry Monroy ruled that the prosecution had presented enough evidence to warrant a trial of the three officers, believed by the prosecution to be the "intellectual authors" of Myrna Mack's murder.

Following Judge Monroy's ruling, Helen Mack and her family, once again, received a number of threats and were harassed in their efforts to push the case forward. (Judge Monroy subsequently resigned from the case because of death threats.) In early 1999, in what appeared to be yet another threat against Helen Mack, her father, Marco Antonio Mack—a well-respected landowner in Guatemala, who was seriously ill—was accused by anonymous persons linked to Guatemalan intelligence units of being involved in drug trafficking. Mr. Mack died a few weeks later.

On April 26, 1999, the anniversary of the murder of Bishop Juan José Gerardi and two days after Mr. Mack's death, a stone wrapped in a plastic bag was left outside the doors of a church in Guatemala City where Helen Mack was attending a funeral mass for her father. The stone is widely believed to have been left as a reminder of the cement block used to kill the bishop. (Bishop Gerardi oversaw the research and writing of the Recovery of Historical Memory (REMHI) report, which provides a detailed account of human rights violations committed during Guatemala's civil war. The report found that the Guatemalan military was responsible for the vast majority of the 150,000 noncombatants killed and the approximately 50,000 people who disappeared during the armed conflict. The bishop was murdered by a blow to the head with a concrete block just two days after the REMHI report was released.) This escalation of threats appeared to be a direct effort to intimidate Helen Mack and her family at a crucial juncture in Myrna Mack's case.

The impending trial of the three former military officers was subsequently postponed when the defense filed a motion asking that the three be tried before a military court. In early September 2000, Judge Otto Marroquín of Guatemala's Constitutional Court (the highest court in the land) rejected the motion and ruled that a lower criminal court had one month in which to set a new trial date for the Mack case. The defendants then filed a motion objecting to the Third Sentencing Court as a venue and requesting a new judge. In November 2000, that motion was rejected by the Fourth Appeals Court. In the spring of 2001, the Third Sentencing Court transferred the Mack case to another court. This development in the case was viewed as a significant setback by the prosecution because it annulled much of the legal work that had taken place on the case since 1999.

The trial was then scheduled to commence on October 10, 2001, in Guatemala City. In late September, just a few weeks before the trial was scheduled to begin, a Guatemalan court provisionally granted a motion brought by the defense that questioned the objectivity of one of the judges scheduled to hear the case. Once again, the trial was postponed. The trial was again rescheduled. After years of delays and numerous preliminary proceedings on various motions, the trial of the three officers finally began on September 3, 2002. The first day of the trial, the three-judge panel remanded the three defendants to jail for the remainder of the trial, citing concerns both for their safety and for possible flight risk.

One month later, on October 3, 2002, Colonel Juan Valencia Osorio was convicted and sentenced to 30 years in prison for ordering Myrna Mack's murder—the maximum sentence allowed under Guatemalan law. The other two officers—General Godoy Gaitán and Colonel Oliva Carrera—were acquitted on the grounds that there was insufficient evidence that they had been directly involved in ordering the murder.

Both the prosecution and defense subsequently appealed the verdict, issuing briefs on both substantive and procedural issues regarding the trial. On May 7, 2003, the Guatemalan Fourth Appeals Court overturned the verdict against Colonel Valencia Osorio. The court also upheld the acquittals of General Godoy Gaitán and Colonel Oliva Carrera. All three men were immediately released from custody. (They had been held in prison pending the outcome of the appeals.)

On June 19, 2003, using a procedure known as cassation, the prosecution filed a second appeal, this time to the Guatemalan Supreme Court, asking that the Fourth Appeals Court's decision be reviewed on both substantive and procedural grounds. The Supreme Court accepted the substantive grounds of the appeal, and, on January 20, 2004, reversed the earlier appeals court decision. The Supreme Court upheld the conviction of Col. Valencia as an “intellectual author” of Myrna Mack’s assassination, confirmed his 30-year prison sentence, and ordered that he be taken into custody.

Helen Mack has indicated that she plans to move forward with a negligence claim that she submitted to the Judicial Discipline Board in August 2003 against the Fourth Appeals Court magistrates for their ruling in this case. A hearing on the facts of the claim was scheduled for October 28, 2003, for the prosecution to present its arguments before the Board. That hearing was suspended after the ability to make a negligence claim of this sort was appealed. The hearing cannot take place until the appeal is resolved.

For more than a decade, while Helen Mack and other Mack family members have sought domestic remedies to bring to justice those responsible for Myrna’s killing, they also pursued justice in parallel proceedings within the Inter-American system. In 1991, Helen Mack and the Lawyers Committee for Human Rights presented a petition before the Inter-America Commission on Human Rights, requesting that the case be fully investigated and adjudicated. In March 1996, the Commission declared the petition “admissible.” Although normally petitioners are required to exhaust remedies in domestic courts before the Commission will admit a complaint, in this case the determination was made that delays and obstacles had so compromised Helen Mack’s ability to obtain effective access to a remedy that the “exhaustion” requirements were deemed inapplicable.

In early 2000, because of Guatemala's failure, at that point, to bring the three military officers charged with ordering Myrna Mack's murder to trial in its own courts, Helen Mack requested that the Commission begin the process of placing the case under the binding jurisdiction of the Inter-American Court of Human Rights in San José, Costa Rica. On March 3, 2000, at a Commission hearing on the Mack case, Guatemalan government officials acknowledged that the State bears responsibility for both Myrna Mack's murder and the State's failure to obtain justice in the case. In June 2001 the Commission formally referred the case to the Court. The Court admitted the case against the Guatemalan government and in February 2003 heard oral arguments.

On December 19, 2003, the Inter-American Court unanimously found Guatemala in violation of Articles 1 (obligation to respect rights), 4 (right to life), 5 (humane treatment), 8 (judicial guarantees) and 25 (judicial protection) of the American Convention on Human Rights. In its 240-page decision, a majority of the Court ordered, among other things, that Guatemala must:

• investigate the facts of the case in order to identify and prosecute all those responsible for the killing, as well as those who covered up the crime;

• guarantee adequate security for the judicial authorities, prosecutors, witnesses, and relatives of Myrna Mack;

• publicly recognize its responsibility in the case;

• establish a scholarship in Myrna Mack’s name and name a street or plaza in Guatemala City after her; and

• pay US $266,000 for material damages and US $350,000 for pain and suffering to members of the Mack family.


Related Links

Guatemala Justice Prevails in the Mack Case (1/23/04)

CHR Report-Guatemala: Human Rights and the Myrna Mack Case (2003)

Conviction in Mack Trial Overturned on Appeal (5/19/03)

Guilty Verdict Announced in Mack Chang Trial (10/4/2002)

The Myrna Mack Case: An Update (1998)

Scientists and Human Rights in Guatemala (1992)