HAVERFORD, Penn. — It has been only a year since a court convicted Gen. Efraín Ríos Montt, a former president of Guatemala, of genocide, a step hailed as a breakthrough for the country’s fragile democracy. And yet Guatemala’s hard-won progress is starting to falter; if nothing is done, it could easily slip back into authoritarianism, violence and disregard for basic human rights.

The trial of General Ríos Montt, who as the unelected president from 1982 to 1983 oversaw the murder of tens of thousands of Guatemalans, was the first time in history that a head of state anywhere was tried and convicted of genocide in a domestic courtroom. It was also supposed to be a major turning point for Guatemala’s court system, which, until recently, punished only 2 percent of all crimes.

But less than two weeks later, the verdict was annulled on procedural grounds. The decision was a cruel disappointment for the victims of General Ríos Montt’s regime, whose expectations had been raised by the trial, and a huge relief for former military leaders, who feared that they might stand trial next, and for powerful businesspeople who financed the country’s civil war.

Nevertheless, as Guatemala faded from headlines, a flurry of political mobilization and maneuvering began. The poor, who had borne the brunt of General Ríos Montt’s regime, were emboldened by the trial and demonstrated en masse when the verdict was annulled.