Police believe the mobile device captured video of Monday's dispute at the Lake Mary house where Zimmerman was living, but the former neighborhood watch volunteer smashed it to pieces and it needs to be examined in a crime lab. Without the video or some other piece of independent evidence, legal experts said it will be hard to build a case because Shellie Zimmerman changed her story about her husband threatening her with a gun and decided not to press charges.
"I think it's severely limited if they can't get anything from an eyewitness or video," said Randy McCLean, a former prosecutor who now practices criminal defense and family law in central Florida.
Shellie Zimmerman, 26, had moved out of the house last month but stopped by with her father Monday to gather some remaining items. Shellie Zimmerman's father owns the house with his wife.
Shellie Zimmerman called 911, saying her estranged husband was in his truck and threatening her and her father with a gun. She also said her husband punched her father in the nose. Hours later, she told police she hadn't seen a gun.
Police said no gun was ever found and the former couple blamed each other for being the aggressor.
"The iPad video is going to be paramount in this case," Zach Hudson, a spokesman for the Lake Mary Police Department.
Hudson said as many as seven people were at the house and they all have been questioned by investigators. He didn't say who they were. Authorities are also looking into whether surveillance video from cameras at the house captured the dispute.
Also, Shellie Zimmerman said on the 911 call that a city worker witnessed the dispute, and if so, that eyewitness and any others could help authorities decide whether to file charges. Florida law allows police officers to arrest someone for domestic violence without the consent of the victim.
Shellie Zimmerman's father and Zimmerman "put hands on each other" but there were no injuries and the father doesn't want to press charges either, Hudson said Tuesday.
When asked if George or Shellie Zimmerman could be charged, Hudson said: "As of right now, it could be either one or it could be no one. It depends what that iPad has on it, what that footage shows."
Zimmerman's attorney, Mark O'Mara, said on Monday his client did nothing wrong and the dispute was typical for a couple going through a divorce. On Tuesday, he said he was not going to represent George Zimmerman in this matter.
"I've come to know them as a family, and it's not a good idea to get in between them," O'Mara said.
Police investigators will turn over all their information to prosecutors, who will then make the decision to file charges or not, said David Hill, an Orlando area defense attorney.
"If nobody is going to cooperate, I don't think anything is going to happen," Hill said.
As of Tuesday, the State Attorney's Office hasn't yet received information on the case, spokeswoman Lynne Bumpus Hooper said in an email.
Shellie Zimmerman's attorney, Kelly Sims, didn't return a phone call or email Tuesday.
Shellie Zimmerman filed for divorce last week. She and her husband separated a month after he was acquitted July 13 in the fatal shooting of 17-year-old Trayvon Martin in 2012 in Sanford, an Orlando suburb less than 5 miles from Lake Mary.
Zimmerman said he acted in self-defense when he shot Martin. He wasn't charged until 44 days after the shooting, leading to protests nationwide from people who believed he should've been immediately arrested.
Demonstrations were organized again after his acquittal. Federal authorities are now reviewing the case the see if Martin's civil rights were violated.
The encounter Monday was the latest in a string of events for Zimmerman since he was found not guilty. He has twice been pulled over on suspicion of speeding and ticketed once. He also appeared in photos online at a gun maker's plant and he helped members of a family from their vehicle following a car wreck.
Shellie Zimmerman was convicted of perjury last month for lying about the couple's finances at her husband's bail hearing for killing Martin.
George Zimmerman has been involved with a domestic case at least once before. In 2005, Zimmerman's former fiancee filed for a restraining order against Zimmerman, alleging domestic violence. Zimmerman responded by requesting a restraining order against his then-fiancee.
Zimmerman blames his arrest and the trial for the implosion of his marriage, O'Mara said, but Zimmerman needs to be a lot more "circumspect" about what he does.
"Anything he does is going to be hyper-focused on and scrutinized," O'Mara said. "Even though I may get away with a little speeding, he can't. It's unfortunate that this is part of the fallout from a case that never should have been prosecuted and he has to deal with this forever, and certainly right now."
Marina Hutchinson in Atlanta and Kyle Hightower in Orlando contributed to this report.
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