Dec. 2, 1980: Maura Clarke, Jean Donovan, Ita Ford, and Dorothy Kazel are kidnapped and murdered by five members of the Salvadorean National Guards in civilian dress. Two of the women were also sexually assaulted.
Dec. 3, 1980: The bodies of the four women are found on a desolate roadside in the vicinity of Santiago Nonualco by a local landowner. The bodies are buried in a shallow grave by members of the state security forces, who do not report the murders.
Dec. 4, 1980: US Ambassador Robert White is informed by church officials that the women have been killed and buried. White goes immediately to the gravesite.
Dec. 6-9, 1980: A group appointed by US President Jimmy Carter arrives in El Salvador to investigate the murders and establishes a Salvadorean Special Investigation Commission to look into the killings.
Dec. 5, 1980: The Carter administration suspends military aid to El Salvador in response to the murder of the nuns.
Dec. 8, 1980: Col. Carlos Eugenio Vides Casanova, head of El Salvador's national guard and later defense minister, informs the US Embassy that after an investigation, he has determined that ''the murders of the nuns could not have been the work of the government.''
Dec. 9, 1980: The FBI arrives in El Salvador to investigate the case.
Dec. 12, 1980: The report by the Presidential Mission concludes that authorities knew ''that four women were brutally murdered and had cause to believe that they were Americans - yet provided no information to the (US) Embassy. There is a high probability that an attempt was made to conceal the deaths.''
Jan. 14, 1981: US military aid, which had been suspended, is resumed because of ''progress in areas of concern to us, especially the investigation of the four American church women.''
Jan. 21, 1981: An internal State Department cable concludes, ''All the evidence we have . . . is that the Salvadorean government has made no serious effort to investigate the killings of the murdered women.''
April 1981: The US Embassy provides Salvadorean authorities with information implicating six members of the National Guard.
May 9, 1981: Six National Guardsmen are placed under arrest for the murders.
December, 1981: Two of the original suspects are released and two new suspects arrested. One of these suspects is later released.
January 1982: One of the newly arrested guardsmen says that he directly participated in the murders and ties four other National Guardsmen to the crime. His account is corroborated later by another guardsman.
Jan. 26, 1982: Two days before the first US presidential certification of aid to El Salvador, Defense Minister Jose Guillermo Garcia announces that the guardsmen will go to trial ''within a very few days.''
Jan. 27, 1982: In another certification report, the US State Department says that they expect ''the date of the trial to be set this fall.''
June 5, 1982: Former Salvadorean President Jose Napoleon Duarte says it may be a year before the trial is held.
Nov. 15, 1982: Salvadorean Judge Bernardo Raudo Murcia orders the case to go to the trial stage. (But appeals then keep the case from going to trial.)
Dec. 10, 1982: The US Embassy in El Salvador reports the trial will take place ''in late January or early February 1983.''
January, 1983: El Salvador's attorney general, Dr. Mario Adalberto Rivera, says it will be two to three months before a trial is held.
July 20, 1983: In its fourth certification report, the US State Department says, ''We are hopeful that the case will go to trial within the next few weeks.''
July 22, 1983: Judge Raudo says the gathering of new evidence will require a six-month delay.
June 1983: Harold R. Tyler Jr., a practicing lawyer and former US federal judge, accepts an appointment by the State Department to determine if the US has done everything possible to advance a prosecution.
Oct. 29, 1983: Judge Raudo orders the case to trial for the second time.
Dec. 3, 1983: Judge Tyler's report is submitted to the State Department and immediately classified.
Feb. 16, 1984: The New York Times reports that Judge Tyler's report concludes that ''it is quite possible that Col. Carlos Eugenio Vides Casanova was aware of and for a time acquiesced in the cover-up'' of this crime.
Feb. 25, 1984: Defense appeals to block the case from going to the trail state are overturned. A Salvadorean appellate court orders Judge Runda to begin trial ''in about two months.''
March 3, 1984: A former Salvadorean military official believed to be Roberto Santivanaz charges that Col. Oscar Edgardo Casanova ordered the killing of the nuns. Colonel Casanova, a cousin of Defense Minister Vides Casanova, was the Army commander in La Paz Province at the time of the murders.