Wrongful execution is a miscarriage of justice occurring when an innocent person is put to death by capital punishment. Cases of wrongful execution are cited as an argument by opponents of capital punishment, while proponents suggest that the argument of innocence concerns the credibility of the justice system as a whole and does not solely undermine the use of death penalty.
A number of people are claimed to have been innocent victims of the death penalty. Newly available DNA evidence has allowed the exoneration and release of more than 20 death row inmates since 1992 in the United States, but DNA evidence is available in only a fraction of capital cases. Others have been released on the basis of weak cases against them, sometimes involving prosecutorial misconduct; resulting in acquittal at retrial, charges dropped, or innocence-based pardons. The Death Penalty Information Center (U.S.) has published a list of 10 inmates "executed but possibly innocent". At least 39 executions are claimed to have been carried out in the U.S. in the face of evidence of innocence or serious doubt about guilt.
Since 1976 the United States has executed over 1,400 offenders: none of them have since been granted a posthumous exoneration.
In the UK, reviews prompted by the Criminal Cases Review Commission have resulted in one pardon and three exonerations for people executed between 1950 and 1953 (when the execution rate in England and Wales averaged 17 per year), with compensation being paid.
Colin Campbell Ross was hanged in Melbourne in 1922 for the murder of 12-year-old Alma Tirtschke the previous year in what became known as the Gun Alley Murder. The case was re-examined in the 1990s using modern techniques and Ross was eventually pardoned in 2008. Capital punishment in Australia was abolished in all jurisdictions, with the last execution taking place in 1967.
Wei Qing'an (Chinese: , 1961-1984, 23 years old) was a Chinese citizen who was executed for the rape of Kun Liu, a woman who had disappeared. The execution was carried out on 3 May 1984 by the Intermediate People's Court. In the next month, Tian Yuxiu () was arrested and admitted that he had committed the rape. Three years later, Wei was officially declared innocent.
Teng Xingshan (Chinese: , ?-1989) was a Chinese citizen who was executed for supposedly having raped, robbed and murdered Shi Xiaorong (), a woman who had disappeared. An old man found a dismembered body, and incompetent police forensics claimed to have matched the body to the photo of the missing Shi Xiaorong. The execution was carried out on 28 January 1989 by the Huaihua Intermediate People's Court. In 1993, the previously missing woman returned to the village, saying she had been kidnapped and taken to Shandong. The absolute innocence of the wrongfully executed Teng was not admitted until 2005.
Nie Shubin (Chinese: , 1974-1995) was a Chinese citizen who was executed for the rape and murder of Kang Juhua (), a woman in her thirties. The execution was carried out on April 27, 1995 by the Shijiazhuang Intermediate People's Court. In 2005, ten years after the execution, Wang Shujin (Chinese: ) admitted to the police that he had committed the murder.
Qo?siletu or Huugjilt (Mongolian:qo?siletu, Chinese:, 1977-1996) was an Inner Mongolian who was executed for the rape and murder of a young girl on June 10, 1996. On December 5, 2006, ten years after the execution, Zhao Zhihong (Chinese: ) wrote the Petition of my Death Penalty admitting he had committed the crime. Huugjilt was posthumously exonerated and Zhao Zhihong was sentenced to death in 2015.
Harry Gleeson was executed in Ireland in April 1941 for the Murder of Moll McCarthy in County Tipperary in November 1940. The Gardai withheld crucial evidence and fabricated other evidence against Gleeson. In 2015 he was posthumously pardoned.
Jiang Guoqing (Jiang is the family name, Chinese: , 1975-1997) was a Republic of China(Taiwan) Air Force private who was executed by a military tribunal on August 13, 1997 for the rape and murder of a five-year-old girl. On January 28, 2011, over 13 years after the execution, Xu Rongzhou (Chinese: ), who had a history of sexual abuse, admitted to the prosecutor that he had been responsible for the crime. In September 2011 Jiang was posthumously acquitted by a military court who found Jiang's original confession had been obtained by torture. Ma Ying-jeou, Republic of China's(Taiwan) president, apologised to Jiang's family.
University of Michigan law professor Samuel Gross led a team of experts in the law and in statistics that estimated the likely number of unjust convictions. The study, published in Proceedings of the National Academy of Sciences determined that at least 4% of people on death row were and are likely innocent. Gross has no doubt that some innocent people have been executed.
Statistics likely understate the actual problem of wrongful convictions because once an execution has occurred there is often insufficient motivation and finance to keep a case open, and it becomes unlikely at that point that the miscarriage of justice will ever be exposed. For example, in the case of Joseph Roger O'Dell III, executed in Virginia in 1997 for a rape and murder, a prosecuting attorney argued in court in 1998 that if posthumous DNA results exonerated O'Dell, "it would be shouted from the rooftops that ... Virginia executed an innocent man." The state prevailed, and the evidence was destroyed.
Thomas and Meeks Griffin were executed in 1915 for the murder of a man involved in an interracial affair two years previously but were pardoned 94 years after execution. It is thought that they were arrested and charged because they were viewed as wealthy enough to hire competent legal counsel and get an acquittal.
Joe Arridy (April 15, 1915 - January 6, 1939) was a mentally disabled American man executed for rape and murder and posthumously granted a pardon. Arridy was sentenced to death for the murder and rape of a 15-year-old schoolgirl from Pueblo, Colorado. He confessed to murdering the girl and assaulting her sister. Due to the sensational nature of the crime precautions were taken to keep him from being hanged by vigilante justice. His sentence was executed after multiple stays on January 6, 1939, in the Colorado gas chamber in the state penitentiary in Canon City, Colorado. Arridy was the first Colorado prisoner posthumously pardoned in January 2011 by Colorado Governor Bill Ritter, a former district attorney, after research had shown that Arridy was very likely not in Pueblo when the crime happened and had been coerced into confessing. Among other things, Arridy had an IQ of 46, which was equal to the mental age of a 6-year-old. He did not even understand that he was going to be executed, and played with a toy train that the warden, Roy Best, had given to him as a present. A man named Frank Aguilar had been executed in 1937 in the Colorado gas chamber for the same crime for which Arridy ended up also being executed. Arridy's posthumous pardon in 2011 was the first such pardon in Colorado history. A press release from the governor's office stated, "[A]n overwhelming body of evidence indicates the 23-year-old Arridy was innocent, including false and coerced confessions, the likelihood that Arridy was not in Pueblo at the time of the killing, and an admission of guilt by someone else." The governor also pointed to Arridy's intellectual disabilities. The governor said, "Granting a posthumous pardon is an extraordinary remedy. But the tragic conviction of Mr. Arridy and his subsequent execution on Jan. 6, 1939, merit such relief based on the great likelihood that Mr. Arridy was, in fact, innocent of the crime for which he was executed, and his severe mental disability at the time of his trial and execution."
George Stinney, a 14-year old black boy, was electrocuted in South Carolina in 1944 for the murder of Betty June Binnicker, age 11, as well as Mary Emma Thames, age 8. The arrest occurred on March 23, 1944 in Alcolu, inside of Clarendon County, South Carolina. Apparently, the two girls rode their bikes past Stinney's house where they asked him and his sister a certain type of flower; after this encounter, the girls went missing and were found dead in a ditch the following morning. After an hour of interrogation by the officers, a deputy stated that Stinney confessed to the murder. The confession explained that Stinney wanted to have intercourse with Betty, so he wanted to kill Mary to get Betty alone; however, both girls fought back and that is when he killed both of them. This case still remains a very controversial one due to the fact that the judicial process showed severe shortcomings. An example can be made out of this case by showing how the judicial system does not always properly orchestrate. He was the youngest person executed in the United States. More than 70 years later, a judge threw out the conviction, calling it a "great injustice."
Carlos DeLuna was executed in Texas in December 1989. Subsequent investigations cast strong doubt upon DeLuna's guilt for the murder of which he had been convicted. Carlos Deluna was executed in 1989 for stabbing a gas station clerk to death. His execution came about six years after the crime was committed. The trial ended up attracting local attention, but it was never suggested that an innocent man was about to be punished while the actual killer went free. Deluna was found blocks away from the crime scene with $149 in his pocket. From that point on, it went downhill for the young Carlos Deluna. A wrongful eyewitness testimony is what formed the case against him. Unfortunately, Deluna's previous criminal record was very much used against him.The real killer, Carlos Hernandez, was a repeated violent offender who actually had a history of slashing women with his unique buck knife, not to mentioned he looked very similar to Carlos Deluna. Hernandez did not keep quiet about his murder, apparently he went around bragging about the killing of Lopez. In 1999, Hernandez was imprisoned for attacking his neighbor with a knife.
Jesse Tafero was convicted of murder and executed via electric chair in May 1990 in the state of Florida for the murders of two Florida Highway Patrol officers. The conviction of a co-defendant was overturned in 1992 after a recreation of the crime scene indicated a third person had committed the murders. Not only was Tafero wrongly accused, his electric chair malfunctioned as well - three times. As a result, Tafero's head caught on fire. After this encounter, a debate was piloted focused around humane methods of execution. Lethal injections became more common in the states rather than the electric chair.
Johnny Garrett of Texas was executed in February 1992 for allegedly raping and murdering a nun. In March 2004 cold-case DNA testing identified Leoncio Rueda as the rapist and murderer of another elderly victim killed four months earlier. Immediately following the nun's murder, prosecutors and police were certain the two cases were committed by the same assailant. The flawed case is explored in a 2008 documentary entitled The Last Word.
Cameron Todd Willingham was executed in February 2004 for murdering his three young children by arson at the family home in Corsicana, Texas. Nationally known fire investigator Gerald Hurst reviewed the case documents, including the trial transcriptions and an hour-long videotape of the aftermath of the fire scene, and said in December 2004 that "There's nothing to suggest to any reasonable arson investigator that this was an arson fire. It was just a fire." In 2010, the Innocence Project filed a lawsuit against the State of Texas, seeking a judgment of "official oppression".
In 2015, the Justice Department and the FBI formally acknowledged that nearly every examiner in an FBI forensic squad overstated forensic hair matches for two decades before the year 2000. Of the 28 forensic examiners testifying to hair matches in a total of 268 trials reviewed, 26 overstated the evidence of forensic hair matches and 95% of the overstatements favored the prosecution. Defendants were sentenced to death in 32 of those 268 cases.
Kirk Bloodsworth was the first American to be freed from death row as a result of exoneration by DNA fingerprinting. Kirk Bloodsworth was a Marine before he became a waterman on the Eastern Shore of Maryland. At the age of 22, he was wrongly convicted of the murder of a nine-year-old girl; she had been sexually assaulted, strangled, and beaten with a rock. An anonymous call to the police claiming that the witness had seen Bloodsworth with the girl that day, and he matched up with the description from the police sketch. Five witnesses claiming that they saw Bloodsworth with the victim, as well a statement in his testimony where he claimed that he "had done something terrible that day that would affect his relationship with his wife", did not help his case. No physical evidence connected Bloodsworth to the crime, but he was still convicted of rape and murder which led to him receiving the death penalty. 
Ray Krone is the 100th American to have been sentenced to death and then later exonerated. Ray Krone was convicted of the murder of Kim Ancona, thirty-six year old victim in Phoenix, Arizona. Ancona had been found nude, fatally stabbed. The physical evidence that the police had to reply on was bite marks on the Ancona's breasts and neck. After Ancona had told a friend that Ray Krone, a regular customer, was going to help her close the bar the previous night, the police brought him in to make a Styrofoam impression of his teeth. After comparing the teeth marks, Krone was arrested for the murder, kidnapping, and sexual assault of Kim Ancona on December 31, 1991. At the trial in 1992, Krone pled innocence, but the teeth mark comparison caused the jury to found him guilty and he was sentenced to death as well as a consecutive twenty-one year term of imprisonment. Krone's family also believed that he was innocent, which led them to spend over $300,000 in order to fight for his freedom, which seemed well worth it since he was eventually exonerated.
In the UK, reviews prompted by the Criminal Cases Review Commission have resulted in one pardon and three exonerations for people that were executed between 1950 and 1953 (when the execution rate in England and Wales averaged 17 per year), with compensation being paid. Timothy Evans was granted a posthumous free pardon in 1966. Mahmood Hussein Mattan was convicted in 1952 and was the last person to be hanged in Cardiff, Wales, but had his conviction quashed in 1998. George Kelly was hanged at Liverpool in 1950, but had his conviction quashed by the Court of Appeal in June 2003.Derek Bentley had his conviction quashed in 1998 with the appeal trial judge, Lord Bingham, noting that the original trial judge, Lord Goddard, had denied the defendant "the fair trial which is the birthright of every British citizen."
Colin Campbell Ross (1892-1922) was an Australian wine-bar owner executed for the murder of a child which became known as The Gun Alley Murder, despite there being evidence that he was innocent. Following his execution, efforts were made to clear his name, and in the 1990s old evidence was re-examined with modern forensic techniques which supported the view that Ross was innocent. In 2006 an appeal for mercy was made to Victoria's Chief Justice and on 27 May 2008 the Victorian government pardoned Ross in what is believed to be an Australian legal first.
There has been much debate about the justification of imposing capital punishment on individuals who have been diagnosed with mental retardation. Some have argued that the execution of people with mental retardation constitutes cruel and unusual punishment as it pertains to the Eighth Amendment to the United States Constitution. While the U.S. Supreme Court interpreted cruel and unusual punishment to include those that fail to take into account the defendant's degree of criminal culpability,[clarification needed] it did not determine that executing the mentally retarded constitutes cruel and unusual punishment until 2002.
This issue was first addressed in the case of Penry v. Lynaugh, in which Johnny Paul Penry had filed a habeas corpus petition in federal district court that claimed his death sentence should be vacated because it violated his Eighth Amendment rights. His reasoning was that he suffered from mental retardation, and numerous psychologists had confirmed this to be factual, indicating that his IQ ranged from 50 to 63 and that he possessed the mental abilities of a six-and-a-half-year-old. Penry's petition was denied by the district court, whose decision was subsequently affirmed by the Fifth Circuit Court of Appeals. Penry would later appeal to the Supreme Court, who ultimately ruled in a five-to-four decision that the Eighth Amendment to the United States Constitution did not categorically prohibit the execution of persons with mental retardation. Following the 1989 Penry ruling, sixteen states as well as the federal government passed legislation that banned the execution of offenders with mental retardation.
Penry was overruled in 2002 by Atkins v. Virginia, which held that the Eighth Amendment's ban on cruel and unusual punishment precluded the execution of the mentally handicapped, but the Supreme Court left the definition of mentally handicapped as something to be determined by the states.