Kimberly LaGayle McCarthy was born on May 11, 1961, in Greenville, Texas. As a young adult, she pursued a career as an occupational therapist, and she worked in a nursing home. During her life, she faced personal challenges. She was briefly married to a man named Aaron Michaels, and they had one son together.

Over time, Kimberly struggled with addiction. She developed a dependency on crack cocaine, which affected her life significantly. In 1990, she faced legal troubles and was convicted of forgery. She also had various other convictions, including charges for prostitution and theft of services.

On July 21, 1997, Kimberly McCarthy contacted her neighbor, Dorothy Booth, claiming she needed to borrow some sugar. When McCarthy arrived at Booth's home, she attacked her. McCarthy stabbed Booth multiple times with a butcher knife, struck her with a candelabrum, and removed Booth's finger to take her diamond wedding ring. Afterward, she stole Booth's purse and car, then pawned the ring to buy crack cocaine.

The following day, McCarthy was charged with murder. Police found evidence linking her to the crime, including Booth's DNA on the murder weapon, which was discovered at McCarthy's home. McCarthy had also used Booth's credit cards at a liquor store and possessed Booth's driver's license.

In 1998, a jury found McCarthy guilty of Booth's murder. During the sentencing phase, prosecutors presented DNA evidence suggesting McCarthy was involved in two other murders of elderly women in 1988. However, she was never charged for those cases. On November 24, 1998, she received a death sentence.

McCarthy successfully appealed her conviction in 2002, but was retried and again sentenced to death later that year. After her final federal appeal was denied in July 2012, her execution was scheduled for January 29, 2013. She received reprieves, delaying her execution to June 26, 2013.

On that date, McCarthy was executed by lethal injection at the Huntsville Unit in Texas. She became the 500th person to be executed by lethal injection in Texas since the state resumed the death penalty in 1976. McCarthy was pronounced dead at 6:37 p.m. Her last words expressed a belief in her faith and stated she was going home to be with Jesus. She was buried at Captain Joe Byrd Cemetery.