Humans are not perfect and they do make mistakes. Because of this there is always the risk that an innocent person could be convicted and even worse, put to death.
Since 1973, 154 people have been released from death row because of innocence. Nationally, one person is exonerated for every 10 that are executed and DNA testing is available in less than 10 percent of all homicide cases.
Cases of Innocence in Colorado:
In 1996 Robert Dewey was convicted of the 1989 rape and murder of Susan Doll in Fort Collins and sentenced to life in prison. After serving almost 18 years, in 2012 he was released due to new DNA evidence. Dewey became the 290th person in the United States to be exonerated by post-conviction DNA testing.
In 1999 Tim Masters was convicted of the 1987 murder of Peggy Hettrick in Fort Collins. He was sentenced to life in prison. Nine years later, Masters was released due to DNA testing, which pointed to an alternate suspect.
In 2012, outgoing Governor Bill Ritter Jr. granted a posthumous pardon for Joseph Arridy. Arridy had been sentenced to death and executed in 1939 for a murder it is now believed that he was innocent of committing. He is also believed to have been severely mentally disabled at the time of his conviction and execution.