An autopsy report shows that the 17 year old died from a gunshot fired at very close range. Traces of THC, a component of marijuana, were found in Martin's system.
Prosecutors have made public mounds of new documents and evidence collected by police on February 26, the night Martin was allegedly shot to death by George Zimmerman.
Photos taken at the police station after the shooting show marks on Zimmerman's face. A paramedic reported he had "bleeding tenderness to the nose and a small laceration on the back of his head. All injuries have minor bleeding."
Zimmerman, charged with second-degree murder, maintains he shot Martin during a struggle. Witnesses also say there was a fight. In the report, the witnesses appear to back up Zimmerman's account of what happened, describing a man on his back with another person straddling him and throwing punches.
An image of the gun Zimmerman used was also released, and we now know that one investigator thought Zimmerman should be charged with manslaughter.
The documents reveal a police officer called the shooting "avoidable" had Zimmerman "remained in his vehicle and awaited the arrival of law enforcement."
"He made a decision to get out of his car in the rain, profile, pursue and confront Trayvon Martin and ultimately kill an unarmed teenager," said Martin family attorney Benjamin Crump.
There is a dispute about who is heard yelling for help on the 911 recordings.
The lead investigator in the case describes reviewing the 911 calls that night, saying he could clearly hear "a male's voice yelling either 'help' or 'help me' 14 times in an approximately 38-second time span. This voice was determined to be that of George Zimmerman."
But one of the reports says after listening to the calls, Martin's father told an investigator the voice was not his son's. However, ABC News contacted the Martin family's attorney. He says after hearing a clearer version of the recordings, Mr. Martin recognized his son's voice calling for help.