Marvallous Matthew Keene was born on July 5, 1973, in Dayton, Ohio. Little is known about his early upbringing, but at the time of the murders in 1992, Keene was a 19-year-old young man with no prior criminal record. Despite his clean record, he would go on to lead one of the most brutal and senseless murder sprees in Ohio’s history.

Keene’s life before the crimes did not indicate any signs of deep criminal behavior. Those who knew him were shocked by the extent of the violence he later unleashed. However, Keene cited emotional strain and family trauma as contributing factors to his mental state. During his sentencing trial, he broke down in tears and told the court that his older brother, Maurice Keene, had been shot and killed in 1991, a loss that deeply affected him. He also spoke about his troubled relationship with his father.

Yet, even with those hardships, Keene never exhibited extreme violent behavior until the events of Christmas 1992. The violence he participated in, and in many cases initiated, seemed calculated, cold-blooded, and driven by a mix of robbery, thrill-seeking, and an intent to silence witnesses.

The Dayton Christmas murders occurred over a period of seventy-two hours between December 24 and December 26, 1992, in Dayton, Ohio. The crimes were committed by a four-person gang known locally as the “Downtown Posse.” The group consisted of Marvallous Keene, age nineteen; his sixteen-year-old girlfriend, Laura Taylor; twenty-year-old Heather Matthews; and Matthews’s seventeen-year-old boyfriend, DeMarcus Smith. Although their exact motivations varied across each killing, the crimes were primarily committed during robberies and to eliminate potential witnesses. In total, the group killed six individuals and injured two others before they were captured by police. Marvallous Keene was later identified as the ringleader of the group and the primary shooter in most of the murders.

The crime spree began on Christmas Eve, December 24, 1992. That day, Keene, Taylor, and Matthews targeted Joseph Wilkerson, a thirty-four-year-old man who was an acquaintance of Taylor. Taylor proposed that Wilkerson would be willing to pay for a sexual encounter involving the three of them. After arriving at Wilkerson’s house under the pretense of engaging in an orgy, the group proceeded to restrain him using electrical cords. Keene held Wilkerson at gunpoint while Matthews and Taylor searched the house for valuables. They discovered a .32 caliber Derringer pistol inside the home, which Keene used to shoot Wilkerson in the chest. Following this, Taylor fired another shot into his head. In an effort to muffle the sound of the gunshots, the killers covered Wilkerson’s body with blankets. After completing the murder, the group fled the scene in one of Wilkerson’s vehicles and returned later to steal the second car.

Later that same day, the group was joined by DeMarcus Smith, and the four conspirators went in search of a second victim. They came upon eighteen-year-old Danita Gullette, who was using a payphone near a convenience store. Keene and Smith approached her while Taylor watched. After demanding Gullette’s shoes and jacket, Smith forced her to undress at gunpoint. Once they had taken her belongings, Smith and Keene opened fire, shooting Gullette multiple times. She died at the scene. The murder appeared to have no purpose other than theft and thrill. When the group returned to their apartment, Taylor was wearing Gullette’s jacket and Smith was carrying her shoes. At the time of her murder, Gullette was a high school senior and a part-time fast-food worker. She was also the mother of a two-year-old daughter.

The group did not stop there. That evening, they made their way back to Wilkerson’s house and spent the night inside his residence. During that night, a third victim was targeted. This time, the victim was Jeffrey Wright, the former boyfriend of Heather Matthews. Smith and Keene went to Wright’s apartment. After an argument, Smith shot Wright four times in the legs. Despite the injuries, Wright was able to flee to a neighbor’s home and survived the attack.

On December 25, 1992, Christmas Day, Keene returned once again to Wilkerson’s home and stole his second vehicle along with additional possessions. Later that day, Taylor lured her nineteen-year-old former boyfriend, Richmond Maddox, out of his parents’ home. Maddox picked her up in his vehicle, unaware that he was being followed by Keene, Smith, and Matthews in a separate car. As Maddox drove through Dayton, Taylor produced her pistol and shot him in the temple. Maddox lost control of the vehicle, and it crashed on Benton Avenue. Taylor exited the car before the crash and rejoined her accomplices. Maddox died at the scene. Although Keene was present during the pursuit, he was not charged with Maddox’s murder because he did not fire the fatal shot.

The following morning, December 26, 1992, the group turned their attention to robbing a local grocery store. Earlier that day, they had robbed a woman named Kathie Henderson at gunpoint and stolen her car. Using the stolen vehicle, they arrived at the Short Stop Mini Market in Dayton, a small corner store owned by the family of thirty-eight-year-old Sarah Abraham. Abraham was working behind the counter that day, accompanied only by a part-time helper named Edward Thompson. Taylor entered the store first to inspect the premises and returned to the group with a report. Keene and Smith then entered the store with handguns. They ordered Abraham to open the cash register and hand over the money. After receiving forty dollars, Keene shot Abraham in the head at close range. Simultaneously, Smith opened fire on two men inside the store. One of the bullets struck Jones Pettus in the abdomen. The other man, Edward Thompson, was missed by the gunfire. Pettus survived the shooting, but Abraham was critically injured. She was transported to the hospital, where she remained on life support until she died on December 30. She left behind three children.

Later on December 26, the group became increasingly paranoid. They believed that some of their acquaintances might report them to the police. Specifically, sixteen-year-old Wendy Cottrill and eighteen-year-old Marvin Washington were suspected of knowing details about the murders and robberies. Keene, Taylor, Matthews, and Smith devised a plan to silence them permanently. They picked up Cottrill and Washington and drove them to a secluded gravel pit in Dayton. Once there, the pair were forced out of the vehicle at gunpoint. Cottrill and Washington insisted they had not spoken to the police and begged for their lives. Keene shot Cottrill while Smith shot Washington. Their bodies were discovered five days later. According to a friend, Cottrill was three months pregnant at the time of her death.

The crime spree ended later that day. Police spotted the stolen car that had belonged to Henderson and began following it. The gang abandoned the vehicle and returned to the house where they had left Wilkerson’s car. Police quickly surrounded the location. Keene, Matthews, and Taylor were arrested while attempting to leave. Smith fled on foot but was apprehended shortly after.

Following their arrests, Keene confessed to several of the murders during police interrogation. He was charged with five counts of aggravated murder and additional charges related to robbery, attempted murder, and kidnapping. He stood trial in front of a three-judge panel in October 1993. The court found him guilty of all charges. On December 10, 1993, he was formally sentenced to death and additional consecutive sentences ranging from 121 to 293 years for the other offenses. Keene was transferred to death row five days later.

Heather Matthews accepted a plea bargain in exchange for avoiding the death penalty. She was sentenced to two consecutive life terms and additional sentences totaling 194 years. She would not be eligible for parole for at least fifty-three years. Laura Taylor and DeMarcus Smith were both tried as adults despite being minors. Each was sentenced to life in prison with parole eligibility only after serving more than one hundred years.

Keene filed multiple appeals over the years, arguing that racial bias influenced the prosecution’s decision to pursue the death penalty against him and not his white co-defendant. The courts rejected his claims, stating that Keene was the triggerman in most of the killings, while Matthews did not personally shoot any victims. Keene’s final appeal was rejected in 2008. The Ohio Supreme Court signed his death warrant in May 2009.

Marvallous Keene was executed by lethal injection on July 21, 2009, at the Southern Ohio Correctional Facility. He was thirty-six years old. He made no final statement before his death. His last meal included steak, jumbo shrimp, french fries, onion rings, fruit, rolls, German chocolate cake, and soft drinks.

As of 2025, his three co-defendants remain incarcerated, each serving life sentences. Heather Matthews has since become involved in prison mentorship programs, while Laura Taylor and DeMarcus Smith continue to serve lengthy terms without eligibility for parole for many decades to come.