The parents of a 4-year-old Palmdale boy pleaded not guilty this week to torture and murder charges stemming from their son’s death last July.

Jose Maria Cuatro Jr., 28, and Ursula Elaine Juarez, 25, are charged with one count each of murder and torture.

Cuatro is also charged with one count of assault on a child causing death, while Juarez is charged with child abuse resulting in death.

The two—who were arrested Sept. 26 by Los Angeles County sheriff’s detectives—reported a drowning in their family pool in the 1200 block of East Avenue S around 4 p.m. July 5, but their son Noah’s injuries later raised suspicions about how he died.

The following week, Sheriff Alex Villanueva announced that an investigation was underway into the boy’s death. The sheriff said Noah lived with his parents and three siblings, who were taken into protective custody.

The boy’s death raised questions about the actions of county social workers who interacted with the family. Noah’s great-grandmother, Eva Hernandez, filed a multimillion-dollar damages claim—the precursor to a lawsuit—against the county last summer, alleging that the boy died despite “countless reports of abuse” that had been made to the Department of Children and Family Services.

“There were at least a dozen calls made to the child abuse hotline and police from people who said they suspected Cuatro and his siblings were being abused,” according to the claim filed on behalf of the boy’s great-grandmother.

The Los Angeles County Office of Child Protection released a report last September that determined DCFS officials acted “appropriately” in their handling of Noah’s case.

The couple could face up to 32 years to life in prison if convicted as charged.