The hallmarks of the law, impartiality and objectivity, are frequently replaced by a flagrant disdain for information and reasoning, resulting in sad and, in retrospect, dangerously poor conclusions.
1. Harry Gleeson was accused of shooting Mary McCarthy on 1940, to cover up his misdeed of having an illegitimate child with her. When Gleeson discovered Mary’s body on his uncle John Caesar’s farm, he was working for him. He was executed in February 1941. He was pardoned by the Irish government seventy-six years later.

Harry Gleeson was charged of shooting Mary McCarthy with guns that his uncle, John Caesar, had purchased. Information about the firearms’ registration was hidden, fake witness statements were issued, and the date of death was changed from November 21 to November 20.
Gleeson had no alibi as a result of this. Gleeson’s aunt and uncle, on the other hand, were never questioned. The Irish Innocence Project at Griffith College and the Justice for Harry Gleeson campaign tried to re-examine the facts.

The investigation was successful in proving his innocence. President Michael D. Higgins granted Harry Gleeson an official pardon on December 19, 2015. [Sources: 1, 2]
2. Joe Arridy, a mentally disabled man with the mental capacity of a five-year-old, was mistakenly executed in 1939 for the murder of Dorothy Drain, a 15-year-old girl. Inmates nicknamed him “the happiest prisoner on death row” because he played with a toy train given to him by the warden while on death row.

Joe Arridy, a 23-year-old man with the IQ of a six-year-old, was found guilty and hanged for the rape and murder of 15-year-old Dorothy Drain on January 6, 1939.While their parents were not home, Dorothy Drain was found dead and her sister injured at their home in Pueblo, Colorado.
This sparked a massive manhunt for the murderer. After Arridy was detained for roaming around the railyards in Cheyenne, Wyoming, the county sheriff, George Carroll, came across him. The sheriff convinced the mentally disabled man to confess to the crime.

Despite the fact that Frank Aguilar had been arrested by police chief Arthur Grady, he was tried for the murder. He admitted to the crime as well.
The two confessions were cobbled together to construct the story that serial killer Frank Auglier had convinced the easily swayed Arridy to join him in the crime. Joe Arridy’s defense team attempted to show that he was mad in order to avoid the death penalty.
Even when alibis testified that he wasn’t even in Pueblo on the day of the murder, they didn’t pursue his innocence. He was found guilty and sentenced to death in a gas chamber.

Robert Perske became interested in the case in 1992. He discovered that Joe Arridy was significantly mentally different as a result of his studies.
When he was on execution row, warden Roy Characterized him as “the happiest man on death row,” who played with toy trains and insisted on ice cream for his last meal. David A. Martinez filed a 400-page petition to seek Arridy’s pardon based on Perske’s book on the case. Governor Bill Ritter granted him an unconditional pardon. [Sources: 1, 2]
3. Cameron Todd Willingham escaped a house fire on December 23, 1991, only to be imprisoned for the deaths of his three daughters. They had died in the fire. His execution was carried out due to faulty investigative procedures, redundant fire science, and swaying witness testimony. The Texas Forensic Science Commission found the claims of purposeful fire to be uncertain and unconvincing many years later.

Cameron Todd Willingham, 36, was executed on February 17, 2004, for the murder of his three daughters, each twins. Amber Louise Kuykendall, two years old, and Kameron Marie Willingham and Karmen Diane Willingham.
In exchange for a reduced sentence, the father refused to plead guilty. He was found guilty of lighting a fire with the intent of harming his daughters.
The persecution was motivated by the fact that the children were unwanted, and Willingham wished to get rid of them.

Another story claimed that he had harmed the children and was trying to conceal it, but Willingham’s wife and the children’s mother, Stacy Kuykendall, testified that he had never abused them. Witnesses who had previously described the distraught father’s desperate attempts to save the children changed their stories after the police suggested he was the perpetrator.
They now testified that Willingham remained cool throughout the incident and never attempted to enter the house. The puddle-like char streaks on the burned floor were key evidence against him.
The science at the time showed that the fire was caused by a liquid accelerant, indicating that it was not an accident. Arson was the cause of the fire.

David Grann conducted an investigative piece on the case in The New Yorker five years after his execution.
According to his findings, advances in fire science and fire investigator analysis indicated that the evidence for arson was insufficient. On July 23, 2010, a panel of the Texas Forensic Science Commission admitted that arson investigators at the time used “flawed science” to prove that the fire was intentionally set. [Sources: 1, 2]