Male Killers

Steve "Clem" Grogan was a member of Charles Manson's Family who participated in the 1969 murder of Spahn Ranch worker and stuntman Donald "Shorty" Shea. Already living and working around the ranch before becoming closely associated with Manson, Grogan joined Manson and fellow Family member Bruce Davis in the attack on Shea after Manson came to believe the ranch hand was an informant. Grogan was convicted of first-degree murder in 1971 and initially sentenced to death, but the trial judge reduced his punishment to life imprisonment. Years later, Grogan cooperated with authorities and led investigators to Shea's concealed remains. He was paroled in 1985, becoming the first Manson Family member convicted of murder to be released from prison.

Steven Arthur Rios was a Columbia, Missouri, police officer who was convicted of murdering 23-year-old University of Missouri student Jesse Valencia in June 2004. Rios had been involved in a secret sexual relationship with Valencia, who was reportedly threatening to reveal the relationship to Rios's police chief. Valencia was found with his throat slashed near his apartment. Rios was initially convicted of first-degree murder and sentenced to life without parole, but the conviction was overturned because of evidentiary errors. At his 2008 retrial, he was convicted of second-degree murder and armed criminal action and sentenced to life imprisonment plus 23 years, with the convictions subsequently upheld on appeal.

Ted Bundy was an American serial killer who murdered multiple young women across several U.S. states during the 1970s. His crimes became widely known due to his ability to use charm and deception to gain victims’ trust. Bundy evaded capture for years, escaped custody twice, and carried out further killings before his final arrest. He was later convicted and sentenced to death, becoming one of the most infamous serial killers in modern criminal history.

Thayne Ormsby is an American man convicted of a 2010 triple homicide in Maine. At the age of 20, he carried out a violent attack resulting in multiple deaths within a single incident. He was later arrested, convicted, and sentenced to life imprisonment without the possibility of parole.

Timothy Gordon Hyder murdered his fiancée, Natalie "Dawn" Du'Mee, at their home in St. Cloud, Florida, on December 1, 2024, after she told him she no longer wanted to marry him and returned her engagement ring. Hyder retrieved a .357 Magnum revolver and shot Du'Mee in the back of the head before instructing her daughter to call 911. He admitted the shooting to investigators and said he had "snapped." Hyder was convicted of first-degree premeditated murder in May 2025 and sentenced to life imprisonment. He remains incarcerated in Florida.

Timothy Ray Jones Jr. was convicted of murdering his five children in South Carolina in 2014 before transporting their remains across several states. Jones, who had become their primary caretaker following the breakdown of his marriage, killed Merah, Elias, Nahtahn, Gabriel and Abigail Jones at the family home near Lexington. He then drove through several states before leaving them in a rural area near Camden, Alabama. Police detained Jones at a checkpoint in Mississippi, and he later directed investigators to the location. In 2019, he was convicted of five counts of murder and sentenced to death, a sentence upheld by the South Carolina Supreme Court in 2023.

Timothy McVeigh was an American domestic terrorist responsible for the 1995 Oklahoma City bombing. Motivated by anti-government ideology, he carried out a large-scale bombing targeting a federal building. He was arrested shortly after the attack, convicted on multiple federal charges, and executed in 2001.

Tomasz Roman Kosowski is a former Florida plastic surgeon convicted of the first-degree murder of attorney Steven Cozzi. Cozzi disappeared from the Blanchard Law office in Largo, Florida, on March 21, 2023, while representing defendants in a civil lawsuit brought by Kosowski. The prosecution alleged that Kosowski's increasingly bitter dispute with Cozzi developed into a planned attack. Investigators found blood in the law firm's bathroom, surveillance footage showing a man believed to be Kosowski removing a large covered cart from the building, and forensic and digital evidence linking Kosowski to the disappearance. Cozzi's body has never been recovered. Kosowski was arrested four days after Cozzi disappeared and charged with first-degree murder. After repeatedly changing legal representation, he ultimately dismissed his attorneys, waived his right to a jury trial and represented himself before Pinellas County Circuit Judge Joseph Bulone. On September 23, 2026, Judge Bulone found Kosowski guilty of first-degree murder. The sentencing phase remains unresolved. The judge found that the murder was committed for financial gain and was cold, calculated and premeditated, but rejected an additional aggravating factor alleging that the murder was especially heinous, atrocious or cruel. A Spencer hearing was scheduled for October 8, 2026, after which Kosowski faces either life imprisonment without parole or the death penalty.