This is just a small portion of the people who we have good reason to believe were either unjustly executed by the state or who were executed too quickly to allow for new information to come to light

https://deathpenaltyinfo.org/policy-issues/innocence/execute...

Note that the time between sentencing and executions vary wildly, 6-20+ years, and all of these people deserved to have a second chance to prove their innocence given that now we can see where the legal requirement of guilt "Beyond a shadow of a doubt" might have left these potentially innocent people go free.