Missouri mother sentenced to 13 years for placing infant in oven, killing her

Mariah Thomas, a 28-year-old Missouri mother, is sentenced to 13 years in prison after pleading guilty to child endangerment resulting in the death of her one-month-old daughter, Za'riah Mae Thomas. In February 2024, police found the infant deceased with severe burns after Thomas claimed she accidentally placed the baby in the oven instead of her crib. Under a plea deal, prosecutors dismissed a first-degree murder charge, and Thomas will serve 11 years after receiving credit for time served.

Discovery of the victim and evidence

• ▪On February 9, 2024, Kansas City police officers responded to a home where they found one-month-old Za'riah Mae Thomas deceased with severe burns.
• ▪Investigators found Za'riah Mae Thomas with blackened clothing and a diaper that appeared to have melted onto her skin from severe thermal injuries.
• ▪Police investigators recovered a baby blanket with significant burn marks from the living room of the home.
• ▪A witness returned to the home after being warned that something was wrong with the baby, smelled smoke, and found Za'riah Mae Thomas dead.

Guilty plea and plea agreement

• ▪As part of Mariah Thomas's plea agreement, prosecutors dismissed a first-degree murder charge.
• ▪On September 22, 2026, Mariah Thomas pleaded guilty to first-degree endangering the welfare of a child resulting in death.
• ▪Judge Sarah A. Castle found that Mariah Thomas entered her guilty plea voluntarily and ruled that she had no mental disease or defect defense.

Sentencing details

• ▪Judge Sarah A. Castle ordered Mariah Thomas to pay $68 to Missouri's Crime Victims' Compensation Fund and waived all other court costs.
• ▪Mariah Thomas was sentenced to serve 13 years in the Missouri Department of Corrections with no probation.
• ▪Due to credit for time already served in custody, Mariah Thomas will serve 11 years in prison.

Custody and detention

• ▪Following her sentencing, Mariah Thomas was returned to the Jackson County sheriff's custody to await transfer to state prison.
• ▪Mariah Thomas was held in custody at the Jackson County jail from her arrest in February 2024 until her sentencing in September 2026.

Thomas's explanation

• ▪A family member told detectives that Mariah Thomas said she thought she put her daughter in her crib but accidentally put her in the oven.
• ▪Mariah Thomas told investigators that she went to put her daughter down for a nap but accidentally placed the infant in the oven instead of the crib.