Garrett was accused of the murder of a Catholic nun that took place on October 31, 1981, when he was 17 years old. According to the prosecution, that morning, Garrett raped, strangled, and killed 76-year-old Sister Tadea Benz in the St. Francis Convent. On November 9, 1981, Garrett, who lived across the street from the convent, was arrested.
Garrett was tried and convicted of the crime. He was held at Ellis Unit, north of Huntsville, Texas, which at the time held men on the State of Texas's death row. He was originally scheduled to be executed on January 6, 1992, but after Pope John Paul II asked for clemency, Governor of Texas Ann Richards gave him a temporary reprieve. After Richards's reprieve, the Texas Board of Pardons and Paroles held a hearing on whether Garrett should receive a commutation to life in prison but the death sentence was retained by a 17 to 1 vote. He was ultimately executed at age 28 at Huntsville Unit on February 11, 1992 by lethal injection.
His final meal request was ice cream. The TDCJ website has stated since at least 2012 that "this offender declined to make a last statement. However, there are last words of Garrett reported from the time of execution re-quoted frequently, and reported by APBnews as: "I'd like to thank my family for loving me and taking care of me. The rest of the world can kiss my ass."
the Last Word which argues that Garrett was in fact innocent of the crime. He argued that Garrett was the victim of overzealous prosecutors and poor defense attorneys.