It's highly consistent.
In other words, if they had found evidence they didn't find, then Zimmerman would be convicted. The only problem with that theory is that there is no such evidence.
No..they absolutely have not been consistent. The whole incident happened during a 7 minute time span. And that's from the time Zimmerman first calls the police to the time he murders Trayvon Martin.
His story has so many holes in it, I am surprised that anyone still defends him.
For example:
Zimmerman can't remember the street names of an area he patrols regularly and has only three streets.
Zimmerman thinks Martin is armed, yet he pursues him into a darkened area used for walking dogs.
Zimmerman says he gives up the chase, yet manages to catch up to Martin.
Zimmerman says Martin appears from behind Bushes, but changes that when it's clear that wasn't the case.
Zimmerman says Martin asks "What's your problem?" which contradicts what the last person heard over the phone.
Zimmerman says that Martin was on top the entire fight, which contradicts what is heard on the phone and the testimony of 2 witnesses.
Zimmerman says that Martin was slamming his head into the concrete which contradicts his injuries.
Zimmerman says that Martin was holding his mouth and nose which contradicts the pictures of him showing no blood smears on his face. It also contradicts the cell phone recording which has multiple voices shouting.
Zimmerman says that after he shot Martin he put him on his belly and stretched his arms out. That contradicts the photos showing Martin's hands under the body.
Zimmerman describes a brutal onslaught of blows to his head that "felt like bricks" which contradict Zimmerman's injuries and injuries to Martin's hands.
Zimmerman says Martin went for his gun and he manages to lock his hand under his arm, grab his gun and shoot him in the chest. That, seems incredibly improbable.