David Grann wrote a riveting piece in last week's New Yorker about Cameron Todd Willingham, executed by the state of Texas in 2004 for allegedly setting a 1991 house fire that killed his three young children. Even before his execution, evidence existed that the fire must have been accidental...

This weekend Milwaukee police finally cracked the case in a string of eight killings that occurred over 21 years, arresting Walter Ellis, a former inmate in state prison. But what should be seen as a victory for law enforcement has left some dismayed. Had Ellis's DNA been collected eight years...