DC300
Hernandez knew he was in prison for life with no chance of parole.
He had no intention of spending 60 more years of his life being somebody else's bitch in a 9x9. He knew of the Massachusetts law that would effectively render him innocent should he die prior to the appeal process being completed.
This piece of shit stayed true to his "hood" code all the way til the very end. Hanging himself was basically him going out on his own terms, avoiding ultimate punishment, and with the premise that he would technically be acquitted as a result - he basically gave a big FU to the family, the prosecutor, and society in general.