Happ, 51, who spent almost half his life on death row, apologized to the family of Angie Crowley before he received the lethal injection at Florida State Prison near Starke, the (Ocala) Star-Banner reported.
The state substituted midazolam hydrochloride for pentobarbitol sodium in its three-drug cocktail. Midazolam hydrochloride, which is marketed as Versed, is given to patients facing surgery to calm them.
While the use of a drug that had not been tested, at least for this purpose, was questioned before the execution, the procedure apparently went forward without mishap.
Crowley, 21, who had moved from Oregon, Ill., to Lauderdale Lakes after getting a job with a Florida travel agency, was kidnapped when she stopped to use a pay phone on Memorial Day weekend in 1986 while driving to meet a friend. Happ, then 24, broke her car window and dragged her out, dumping her body where it was found by a fisherman.
Crowley's two brothers and two sisters witnessed the execution with other relatives. Happ addressed them before he died, confessing to the killing, The Florida Sun-Sentinel reported.
"For the sake of her family, loved ones and all concerned, it is to my agonizing shame that I must confess to this terrible crime," he said.
Chris Crowley told reporters afterward he still has not forgiven his sister's killer.
"The fact that he admitted it -- apologized for it -- was a shock," he said. "He did it, I think, probably for himself."
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