Mr. Zimmerman’s attorney, Craig Sonner, has said his client’s nose was broken in a fight with Trayvon. The police report of the incident, written up in the squad car that arrived in response, says Zimmerman was bleeding from the back of his head.

Yet police video taken Feb. 26, released to the news media March 29, shows an apparently uninjured Zimmerman arriving at police headquarters, hands cuffed behind his back. There are no bandages, no blood, and no swelling visible.

This question is important because it could help prove or disprove Zimmerman’s account of his encounter with Trayvon. He says Trayvon surprised him after he had returned to his vehicle, floored him with one punch, and then beat his head on the ground, according to the police incident report. A broken nose and cuts on the back of the head would be consistent with this account.

On the other hand, if Zimmerman were unhurt or not seriously injured it would call his truthfulness into question. Mr. Sonner said March 29 on the "Today" show that the video is “grainy,” and that his client could have been cleaned up in the squad car. But Trayvon’s family noted that in the tape Zimmerman does not look like someone who recently was fighting for his life.

“I believe that this video is icing on the cake,” said Sybrina Fulton, Trayvon’s mother.

It is likely that at a trial the facts could be established concerning the extent of Zimmerman’s injuries. Responding officers would have to testify about what the neighborhood watch captain looked like when they found him, and whether they offered him aid. As "Today" show host Matt Lauer noted March 29, there should be X-rays or other medical evidence if Zimmerman sought treatment for a broken nose.