During its 12 years of existence, the United Nations-backed International Commission against Impunity in Guatemala, or CICIG, pursued corruption investigations into high-level political players and business figures. The commission’s efforts resulted in hundreds of arrests and indictments, including of a former president, Otto Perez Molina, and his vice president, in 2015. CICIG’s work also helped build anti-corruption-related capacity and expertise among Guatemala’s legal community.

But CICIG was forced to shut down last year after then-President Jimmy Morales refused to renew its mandate. Since then, many judges and prosecutors have faced a campaign of harassment, verbal attacks and death threats, forcing some to flee the country. ...