SANFORD, Fla. -- A public safety expert called by the defense says George Zimmerman's physical capabilities were inferior to those of 17-year-old Trayvon Martin.
Former police officer Dennis Root was called as a witness Wednesday by defense attorneys.
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Root testified that Martin was in better physical shape than Zimmerman, and that the neighborhood watch volunteer wasn't any athlete.
"He would find himself lacking when compared to Mr. Martin," Root said of Zimmerman.
Martin was unarmed and returning from a store when he was fatally shot by Zimmerman, a neighborhood watch volunteer, during a struggle on a dark, rainy night in February 2012. Martin was black and Zimmerman identifies himself as Hispanic. Some civil rights activists argued that the initial delay in charging Zimmerman was influenced by Martin's race. Zimmerman has pleaded not guilty to second-degree murder and says he shot Martin in self-defense.
Root is a former law enforcement officer training instructor, who now acts as a consultant to analyze if use of force is justified.
Root said for people in a fight, time is of the essence.
"If you haven't won fight in 30 seconds change tactic," Root said.
Root testified that it's not just the gun that poses a threat.
"A firearm is as safe as the person holding it," said Root.
Prosecutor John Guy zeroed in on that point.
"An irresponsible person can be really dangerous," said Guy.
Root said he approached the defense to help in the case, and the state questioned if he did that to help his business.
Earlier, a judge ruled that Martin's cellphone texts on fighting and a defense animation depicting the fight between Martin and Zimmerman won't be introduced as evidence at Zimmerman's trial.
Judge Debra Nelson made her ruling Wednesday, a day after she heard arguments on the matter.
The judge says the animation can't be introduced as evidence that can be reviewed by jurors during their deliberations, but defense attorneys may be able to use it during closing arguments.
A defense witness said he made a recreation of what happened the night Zimmerman killed Martin. He said he used Zimmerman's account and information from attorneys to create the video showing Martin in a hoodie punching Zimmerman.
The judge says she agrees with prosecutors' objections to introducing the 17-year-old's text messages.