Damien Echols who along with Charles Jason Baldwin and Jessie Misskelley Jr. were released from prison on August 19, 2011.  Known as the West Memphis Three convicted of the Robin Hood Hills child murders in which three eight year old boys were killed in West Memphis, AR. 
Their convictions were not overturned.  Instead they agreed to an Alford Plea. 

Jason Baldwin one page letter from prison.  Signed, "Jason".

Charles Jason Baldwin Signed Prison Letter