The story of Troy Davis was a controversial one. Officials in Georgia executed the death row inmate on Wednesday, pronouncing him dead at 11:08 p.m.
Davis, 42, was accused of murdering a police officer in 1989. He was convicted of the slaying of Officer Mark MacPhail in 1991. Since his arrest, Davis has repeatedly said he was an innocent man.
And inside the death chamber on Wednesday, his pleas were no different. Davis told the officer's family while on his death bed that he was sorry for your loss, but I did not personally kill your son, father and brother. I am innocent, witnesses reported him saying.
He also had these words to say.
The incident that night was not my fault, I did not have a gun, Davis said to all who gathered for the execution.
Davis also urged people to continue to fight and look deeper into this case so you can really can finally see the truth.
For those about to take my life, may God have mercy on your souls. May God bless your souls, Davis told prison staff.
But his case isn't the only controversial one that the U.S. has seen. Here are a few other recent and old cases that have been reported in the media over the years.
Duane Buck: Last week, the U.S. Supreme Court blocked the execution of Duane Buck, a convicted murderer from Houston who said prosecutors used his race to persuade the jury to give him a death sentence rather than life in prison.
The high court made the decision to temporarily spare Buck, 48, the death penalty on grounds that the jury at his sentencing hearing was told he's a public danger because of his race. This stemmed from the testimony of a psychologist who said that black criminals were more likely to commit future violence than criminals of other races. Buck was convicted of killing his ex-girlfriend and her friend in 1995.
Cameron Todd Willingham
Willingham was convicted of murder and executed for the deaths of his three young daughters. The children died by fire at the family's home and Willingham managed to escape with minor burns. Prosecutors say Willingham was the one who started the fire in an attempt to cover up abusing the girls. But there wasn't any evidence of abuse and Willingham wife said to authorities he never abused his children.
In 2009, an investigative forensic report came out from an expert hired by the Texas Forensic Science Commission, which doubted the claims of arson. The fire department disputed the report, noting that things were overlooked.
Reports are that the court relied on the testimony of two psychologists who had never met Willingham. But the Texas Board of Pardons and Paroles and Gov. Perry didn't stop Willingham's execution in 2004.
She was sentenced to death by lethal injection for reportedly using sex and money to arrange the killing of her husband and stepson in 2002. Lewis was the first woman to die by lethal injection in the state of Virginia and was the only woman on death row in the state prior to her execution. There was much debate in this case because of her gender and her mental capacity, as testing has put Lewis' IQ two points above what is classified as intellectually disabled.
Lewis was executed on Sept. 23, 2010.
Blair spent 14 years on death row for a crime officials later found that he didn't commit. He was exonerated in 2008 after DNA evidence proved that he didn't murder seven-year-old Ashley Estel in 1993, who disappeared in a Dallas park and was found strangled. Eyewitnesses placed Blair at the scene where the body was found and the jury in that case reportedly took 27 minutes to convict him.
See the faces of those listed above in the slideshow that follows.