As a volunteer Emergency Medical Technician serving on the emergency squad in my community, I can offer a little bit of insight into the information released by the special prosecutor, Angela Corey.
The most useful piece is the "Fire Department Report", on page 182. The Fire Department response that night included an EMS rescue rig – R38 – staffed by one regular EMT and one paramedic EMT.
From the report we can also see that emergency dispatch only requested BLS – a basic life support rig – and ruled out the need for an Advanced Life Support unit (ALS). We can presume that means that the emergency dispatcher received information from first responder police officers on scene that led them to conclude no need for ALS.
The Sanford Fire Department rig R38 arrived on the scene at 19:27. That aligns with police narratives that state that they began CPR on Trayvon Martin around 19:22 and continued for approximately six minutes until R38 arrived.
The paramedic on the scene, Michael Brandy, states that he checked for signs of life, including EKG readings, and found none. At 19:30 Trayvon Martin was pronounced deceased. (continued below)
In the meantime, George Zimmerman had been taken into custody and was sitting in the back of a police patrol vehicle. The officer who first accosted Zimmerman noted that he was bleeding from his nose and the back of his head. At 19:40 the EMS team from R38 first made contact with Zimmerman. At 19:51 they reported to dispatch that they were available, meaning back in their rig with all equipment properly stowed.
Their observations and treatments over the next minutes are detailed in their "run sheet" – the written report released yesterday.
At 19:41 they make their initial assessment, noting that Zimmerman's respiration, pulse, pupil reaction, and skin condition are within normal ranges. They do a neurological assessment (Glasgow Coma Scale); Zimmerman's score is the highest possible – 15 (eye response, alertness and orientation, able to understand and respond to verbal commands, full motor control).
On more detailed physical examination, they note abrasion to his forehead, bleeding from his nose, and a one-inch laceration at the back of his head (occipital part of skull – the lower back part that juts out the most). There is minor bleeding from his injuries, and his nose is painful and tender when palpated (felt by touch). Zimmerman has good circulation in all his extremities, no tingling or numbness. He tells them that he did not lose consciousness, and has no pain in his neck or back, which might have indicated spinal column injuries. The only treatment given is to wipe the blood clean. No bandages are applied, which implies the bleeding has stopped. They offer to take Zimmerman to the hospital to be examined by a doctor if he's concerned about any of his injuries, but Zimmerman declines.
All of this probably took about five minutes or less. The paramedic and the EMT would have then gathered up all their equipment, recorded their notes, and restored their rig to ready condition. They reported that they were available for new emergency calls at 19:51 – eleven minutes after first making contact with George Zimmerman.
What is not detailed in their report are any injuries or signs or symptoms of severe head trauma. If a patient's head had been repeatedly bashed onto a sidewalk, we would expect to find abrasions, deeper and multiple lacerations, much more bleeding, as well as contusions and swelling. Absent obvious signs, Zimmerman still would have been taken to the hospital if the paramedic had any indication at all that Zimmerman's head had been pounded on pavement, even if based only on what Zimmerman told him or pain that he described.
While being taken in to police headquarters by Officer Smith, the first officer on the scene, Zimmerman does complain once about feeling light-headed. Smith offers again to drive him to the hospital, but Zimmerman tells him that he's OK, he'll be fine. Officer Smith files a subsequent report stating that he kept continuous observation of Zimmerman throughout the time he was in custody until Zimmerman left, and that at no time did Zimmerman exhibit any signs of head pain or mention again that he felt light-headed.
There is one plausible theory of the events that can be supported by all of the available evidence, making the fewest assumptions and requiring the least complexity to explain.
1. At initial encounter, Zimmerman shouted at Martin. (Deep loud voice is heard before cries for help.)
2. Trayvon Martin punched Zimmerman in the nose and Zimmerman fell backward, striking the back of his head on the edge of the sidewalk. (Most likely mechanism of injury for wounds observed on Zimmerman and abrasions on Martin's knuckles.)
3. Zimmerman held objects in both of his hands when struck in the face, and did not want to let go of at least one of those. (Assumption: If his hands were free when falling backward, he would have broken his fall and not struck his head.)
4. One of those objects was a small black flashlight. (Found on ground nearby.)
5. The other object may have been Zimmerman's handgun. (Assumption – subsequent events are based on this assumption being true.)
6. If the second object were Zimmerman's handgun, that would indicate Zimmerman had pulled a gun on Trayvon Martin. In that case, Martin had no chance to flee, and could either submit to an armed and threatening stranger, or to try to fight, by punching him in the face as hard as he could.
7. If Martin observed that Zimmerman kept control of his handgun after falling, Martin may well have jumped toward Zimmerman to try to take the handgun away. (One eyewitness reported seeing Martin on top of Zimmerman, struggling.)
8. Martin was not successful; he did not control Zimmerman's handgun at any time. (Indisputed fact.)
9. Zimmerman regained his footing, may have yelled at Martin in anger at that time, while holding his gun on Martin. (Alternate occasion for deep shouting heard by witnesses.)
10. Martin began crying for help and pleading for his life. (Subsequent sounds of a younger person's higher voice crying for help heard by several witnesses and recorded on one 911 call.)
11. Zimmerman shot Martin in the chest. Martin fell forward. (Martin's body was found face-down.)
12. Zimmerman knelt down to see if Martin was dead. (Witnesses report seeing larger man kneeling over smaller man, then getting up.)
This is an "Occam's Razor" scenario because it doesn't require a lot of unsupported assumptions, and it fits all of the known evidence.
Inside Zimmerman's head, he's just been hit in the face, hard, by a young man he suspects is a criminal, and he had to struggle to keep the man from taking his gun away. Now the young man is crying his head off, alarming residents. Zimmerman knows police will probably arrive soon. His face hurts, perhaps the back of his head hurts too. He may not be thinking perfectly clearly, but he must know that it won't look good for him to be found holding a gun on an unarmed young man. He may be afraid that if he turns his attention away from the boy for a second, he might either run away or try again to grab his gun. The only way, in his mind, to resolve the situation, to make the screaming stop, to remove the threat that the young man would either flee or fight him again, is to pull the trigger. An ill-considered, stupid decision, but set in motion by all the other imprudent decisions he made up until that moment.