In 7 of the 13 cases, the exoneration occurred in whole or in part because the true killer or killers confessed or admitted to the crime for which the innocent defendant had been sentenced to die. In each case, the true killer was identified through unpredictable events outside the efforts or procedures of the legal system. The fortuities of such exonerating events are clear. Two of the death-row inmates were exonerated only after a new witness came forward with evidence that destroyed the credibility of the prosecution's chief witness. Other cases led to exoneration when DNA results excluded the sentenced men as the killers. DNA testing, however, is an option in only a small minority of capital cases. Most capital cases yield no biological evidence susceptible to forensic analysis. In addition to the factor of fortuitous events, the exonerations revealed the inherent fallibility of any human enterprise. On another level, the exonerations show the problems related to unrecorded confessions, eyewitness identification, jailhouse snitches, bad lawyering, prosecutorial misconduct, and various other vices that plague the criminal justice system. It is clear, therefore, that these cases cannot be interpreted to show that the system works well at uncovering wrongful convictions. In essence, the men exonerated were lucky. If the fortuitous events had not occurred, these innocent men would have been executed.