A South Florida man convicted of killing his best friend in a middle school bathroom in 2004 and who died in prison earlier this year had a heart condition and died of natural causes, according to an autopsy released Monday.
Michael Hernandez, who was 14 years old at the time of the murder, was 31 years old when he died behind bars in May.
According to the autopsy, Hernandez was morbidly obese at 5-foot-10 and 285 pounds, and had cardiac dysrhythmia.
Hernandez was sentenced to life in prison after he killed 14-year-old Jaime Gough at Southwood Middle School. Hernandez stabbed Gough more than 40 times at the Palmetto Bay school before hiding his knife in his backpack and going to class.
At his 2008 trial, jurors rejected Hernandez's claim of insanity and convicted him of first-degree murder.
Trial testimony showed Hernandez kept a journal listing people he wanted to kill, including his own sister, and had been fascinated with other serial killers such as Ted Bundy and Jeffrey Dahmer, adding that he felt he was on a mission to "cleanse the planet" by killing.
In 2016, a new sentencing hearing for Hernandez was mandated after the U.S. Supreme Court ruled in 2012 that juveniles could not automatically be sentenced to life without chance of parole, as Florida law required when Hernandez was sent to prison. The decision was later made retroactive to older cases.
After the second hearing, a Miami-Dade County judge agreed to send Hernandez back to prison for life.
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