Even a detective who interrogates the neighborhood watch leader in an audio recording points out inconsistencies in his story, particularly Zimmerman's claim that Martin confronted him, punched him and slammed his head onto the ground when the teenager had no prior history of violence.
Detective Chris Sereno asks Zimmerman whether he was profiling Martin because he was black, a claim Martin's parents have made.
"You know you are going to come under a lot of scrutiny for this," Sereno said. "Had this person been white, would you have felt the same way?"
"Yes," said Zimmerman, who father is white and his mother Hispanic.
The video and audio tapes released by Zimmerman's attorney give Zimmerman's most detailed account yet of what led to the Feb. 26 shooting. They were released almost a week before Zimmerman's second bond hearing on a second-degree murder charge, and on the heels of unflattering telephone calls capturing Zimmerman and his wife talking in code about using money collected for a defense fund to pay credit cards.
Zimmerman claims he shot the unarmed 17-year-old Martin teen in self-defense, under Florida's "stand your ground" law.
Martin's parents have said Zimmerman was the aggressor. They said Martin was walking back from a convenience store through the gated community in Sanford when Zimmerman spotted Martin and started following him.
In the video, Zimmerman said he grabbed his gun from a holster on his waist before Martin could get it, and shot Martin once in the chest as they fought on the ground outside townhomes in a gated community. After firing, Zimmerman said he thought he missed.
"He sat up and said, 'You got me. You got me, or something like that,'" Zimmerman said.
Zimmerman said Martin had been on top of him, slamming his head against the ground and smothering his mouth and nose with his hand and arm. The tape shows two butterfly bandages on the back of Zimmerman's head and another on his nose. There are red marks on the front of his head.
"It felt like my head was going to explode," he said.
Criminal defense lawyers who reviewed the video for The Associated Press and have no connection to the case said there were some parts that didn't add up.
"He came across as being straight-forward," attorney David Hill said. "I didn't see him being too slick on the details."
Hill said the video didn't show him to be the zealous "cop-wannabe" that Martin's parents have portrayed.
Zimmerman claims Martin confronted him after the neighborhood watch leader had given up searching for him and was walking back to his truck. But there doesn't appear to be a place to hide in the area where Zimmerman says Martin suddenly appeared, Hill pointed out.
Zimmerman's injuries also don't appear to be consistent with the severity of the attack he described, Hill said.
Attorney Blaine McChesney said he found parts of Zimmerman's re-enactment difficult to envision, such as his account of how he was able to reach for his gun with Martin on top of him. Zimmerman said he got on top of Martin after the shooting to restrain him.
"I also find it strange that Zimmerman would have attempted to use both his arms to hold Martin facedown, re-holstering his firearm, given those circumstances," McChesney said. "Once out from under Martin's alleged attack, it would have been more logical to hold Martin at gunpoint from a few feet away until police arrived."
In one of the audio recordings, Sereno tells Zimmerman three days after the shooting that Martin was a "good kid, mild-mannered kid."
Sereno tells Zimmerman that Martin, an athlete with an interest in aeronautics, was "a kid with a future, a kid with folks that care." The detective said Martin only had a bag of Skittles and an iced tea on him when he died.
"Not a goon," Sereno said.
He asked Zimmerman to explain why he doesn't have bruises on his body or broken ribs. The two dozen punches Zimmerman claims he took are "not quite consistent with your injuries," Sereno said.
Benjamin Crump, the attorney for Martin's parents, couldn't immediately be reached for comment Thursday. But appearing on CNN's "Piers Morgan Tonight," Crump said Zimmerman's credibility is the issue.
"Everybody's going to have to look at this for what it is," Crump said. "You've got objective evidence, and then you've got George Zimmerman's versions. You put them up against one another and we know that written statement that he did that night doesn't match up to that 911 tape.
"And there are other inconsistencies, and when we see the lie, we've got to call it out and say, there's his credibility again, and that's the important thing."
Zimmerman called police after spotting Martin walking around the neighborhood and the dispatcher told him not to follow the teen. For reasons that are still unclear, Zimmerman kept up his pursuit, even getting out of his truck. He lost sight of Martin and was walking back to his truck when Martin confronted him, Zimmerman said.
"Do you have a problem?" Zimmerman said, quoting Martin.
If Zimmerman's account his accurate, he has a viable "stand your ground" defense, McChesney said.
Zimmerman's attorney has the option of asking for a "stand your ground" hearing in which he will present Zimmerman's account to a judge and ask that the charge be dismissed without going to trial.
Zimmerman's second bond hearing will be June 29. His $150,000 bond was revoked earlier this month after prosecutors said Zimmerman and his wife, Shellie, misled the court about how much money they had available for bail. Shellie Zimmerman was charged last week with making a false statement.
Defense attorney Mark O'Mara said his client will be shown to have told the truth about the incident, even though the statement regarding the Zimmermans' finances was shown to be false.
"The attacks on Mr. Zimmerman's credibilities are going to pale in comparison to the undeniable, objective evidence," he said.
Associated Press writers Freida Frisaro, Kelli Kennedy, Laura Wides in Miami, Greg Schreier and Bernard McGhee in Atlanta and Brent Kallestad in Tallahassee contributed to this report.