A Guatemalan court has ruled that former dictator Gen. Efraín Ríos Montt will receive a new trial on charges of genocide, despite claims from his legal team that the 89-year-old is suffering from dementia.

In 2013 Ríos Montt was found guilty of ordering the mass killing of Maya Ixil Indians in the early 1980s, but the conviction was overturned 10 days later on a technicality.

The ex-dictator, who came to power in 1982, was to serve 80 years in prison for his connection to the killings of 1,771 people.

Tuesday’s court decision has set a new trial for January, and made provisions that the hearing must take place behind closed doors were reporters will not be allowed to cover any of the proceedings, reports the New York Times. Ríos Montt, if found guilty, cannot be sentenced, but the court would send him to detention at home or in a hospital.

Héctor Reyes, a lawyer at the Center for Legal Action on Human Rights who represents the Maya Ixil victims says that a new trial is needed in order to “demonstrate the facts that serious human rights crimes were committed.”

“They cannot remain in impunity,” Reyes told the New York Times in a phone interview.

Shortly after Rios Montt was declared mentally unfit for trial, Pamela Yates, a filmmaker and journalist who has spent decades covering Guatemala, spoke to NPR about what 2013 trial had revealed.

Speaking of how Mayan Indians in the Maya Ixil region of the Guatemalan Highlands were killed, Yates noted, "The genocide in Guatemala, which is the sole genocide of the Americas in the 20th century, is not taught in Guatemala[n] high schools.”

“It's not taught in the colleges. And so many people don't believe the genocide happened. Now they can no longer believe that,” she said.