Oklahoma has executed a man who was convicted of killing two women aged 83 and 93.
As the curtains opened, Lott looked over at his brother, who raised his fist and nodded. Lott made no final statement. He again looked at his brother in the first row of the viewing room as the drugs were pumped into his body, then Lott's eyes closed. He started breathing heavily and gasped for air three times.
Following the pronouncement of death, corrections workers tried to draw the curtains, but one would not close despite repeated attempts. They ended up hanging a white sheet over the window.
An Oklahoma County jury convicted Lott of two counts of first-degree murder in the deaths of Anna Laura Fowler, 83, in September 1986 and Zelma Cutler, 93, in January 1987. He was also convicted of raping the women.
State and federal courts denied Lott's appeals.
Ms Fowler lived alone in Oklahoma City when Lott broke into her home through the back door and attacked her on September 2, 1986.
Authorities said Ms Fowler was raped and a knotted cloth was used to bind her hands. She had multiple injuries, including rib fractures and bruising on her wrists, hands, eyes, lips and cheeks. She died from asphyxiation, and her grandson found her dead on her bed the next morning.
Ms Cutler's home was across the street from Ms Fowler and she also lived alone. Police found her dead on her bed on January 11, 1987. The electricity to her home had been shut off at the breaker box and the phone wire had been cut. She had been raped and had multiple rib fractures and bruising.
In November, the Oklahoma Pardon and Parole Board voted 4-1 to deny commuting Lott's death sentence to life in prison.
Ms Fowler's son Jim urged the board to spare Lott's life "and let him rot in that damn cell".
Oklahoma is scheduled to execute another inmate before the end of the year. Johnny Dale Black, 48, is to be executed on December 17 for the 1998 stabbing death of a horse trainer.