Ronald Gene Simmons Sr. was born on July 15, 1940, in Chicago, Illinois, to William and Loretta Simmons. His early childhood was marked by instability and family relocation after his father’s death in 1943 and his mother’s subsequent remarriage to William D. Griffen of the U.S. Army Corps of Engineers. Frequent moves across Arkansas exposed him to strict discipline and limited social stability, conditions that some later connected to his obsessive need for control. As a child, relatives described him as a bully and an emotionally volatile boy who often abused animals and tormented his siblings.

At age 17, Simmons left school and joined the U.S. Navy in 1957. He earned his GED and served in Guam and Washington State before meeting Bersabe Rebecca “Becky” Ulibarri, whom he married in 1960. Together, they had seven children over nearly two decades. Simmons later transferred to the U.S. Air Force in 1963, serving for more than 20 years as an administrative specialist and eventually achieving the rank of Master Sergeant. His service record was notable for discipline and decorations, including the Bronze Star and the Vietnam Gallantry Cross. He retired in 1979 after posting consistently excellent evaluations.

Behind his military discipline lay a private life of abuse and control. Family members and acquaintances later testified that Simmons exercised complete dominion over his wife and children—isolating them from the outside world, forbidding his wife from using a telephone, and censoring their mail. He insisted on strict obedience and often used intimidation to maintain his authority at home. His wife Becky was reportedly terrified of him but remained loyal for the sake of their children.

In 1981, while the family was living in Cloudcroft, New Mexico, Simmons was investigated for incest and child sexual abuse after impregnating his 17‑year‑old daughter, Sheila. The case resulted in criminal charges, but before his arrest, Simmons fled New Mexico with his entire family, resettling in Arkansas. The charges were eventually dismissed when authorities could not locate him or persuade Sheila to testify further.

Over the next six years, Simmons moved frequently between low‑paying jobs and kept his family in increasing isolation at a rural property near Dover, Arkansas, which he named Mockingbird Hill. Neighbors and employers described him as quiet, withdrawn, and controlling, with a cold, piercing stare. His home had no working toilet, and family members were forbidden to use a telephone or communicate freely. By the mid‑1980s, his older children had moved out and started their own families, but Simmons remained a dominant, resentful figure. Friends and relatives later observed that he was angry about losing control over his family and had become increasingly paranoid and bitter in the months leading up to the killings.

In late December 1987, Ronald Gene Simmons decided to kill his entire family. On December 22, he first killed his wife, Rebecca, and his eldest son, Gene, using a crowbar and a .22-caliber pistol. He then killed his three-year-old granddaughter, Barbara, by strangling her. All the bodies were hidden in a cesspit he had made the children dig.

After waiting for his other children to come home for Christmas break, Simmons told them he had gifts. He first killed his 17-year-old daughter, Loretta, by strangling and drowning her in a rain barrel. He continued killing his other children, Eddy, Marianne, and Becky, in the same manner, and also placed their bodies in the cesspit.

On December 26, Simmons invited more family members for the holidays. The first victims he killed were his son Billy and his daughter-in-law, Renata, both shot dead. He then drowned their 20-month-old son, Trae, and shot his oldest daughter, Sheila, along with her husband, Dennis. He also strangled Sheila's seven-year-old daughter, Sylvia, and his other grandson, Michael, who was just over a year old. After all the murders, he laid the bodies out in neat rows in the living room, covering them with coats and other items.

On December 28, Simmons went on another shooting spree. He drove to Walmart and bought another gun. His first target was a law office where a secretary named Kathy Kendrick worked. Simmons shot and killed Kendrick, then moved to an oil company office, where he shot the owner, Russell "Rusty" Taylor, wounding him. He killed James David Chaffin, who was an employee at that location, and then shot at another employee but missed.

He kept going to Sinclair Mini Mart and shot two more people there. His last stop was the Woodline Motor Freight Company, where he shot his former supervisor, wounding her. Finally, he ordered an employee to call the police. When they arrived, he surrendered without resistance.

Simmons was arrested and later convicted for the murders. He faced trials for the shootings of Kendrick and Chaffin first, then for the murders of his family. He received the death penalty in both cases. He refused to appeal his death sentence and was executed by lethal injection on June 25, 1990.