Trayvon Martin shooting: George Zimmerman has ties to Manassas
After Martin encountered Zimmerman, the girl thought she heard a scuffle "because his voice changes like something interrupted his speech," Crump said.
The phone call ended before the girl heard gunshots. The last call was at 7:12 p.m.
Police arrived at 7:17 p.m. to find Martin lying face down on the ground.
Zimmerman was handcuffed after police arrived and taken into custody for questioning, but was released by police without being charged.
Police have interviewed Zimmerman twice since then. Crump called the treatment patently unfair and asked if Martin would have received the same treatment if he had been the shooter.
"We will not rest until he is arrested.
The more time that passes, this is going to be swept under the rug," Crump said.
Crump said he plans to turn over information about the call to federal investigators; a grand jury in Seminole County is also likely to subpoena the records.
The Florida Department of Law Enforcement is also involved in the state case.
Former federal prosecutors said there are limitations to a Justice Department civil rights probe, which typically would involve a sworn law enforcement officer accused of abusing his authority.
In this case, they said, it's not clear whether Zimmerman had any actual law enforcement authority or if the Sanford Police Department did anything improper.
Zimmerman had a permit to carry a gun, but it was not required for his neighborhood watch patrol.
"I think the community has the feeling that there's some type of cover-up," said Jeffrey Sloman, former U.S. attorney in Miami.
"At least the department's involvement makes sure it gets some review. He wasn't a police officer.
I'm sure that this is going to be a tough case to prosecute."
Authorities may be hamstrung by a state "Stand Your Ground" law that allows people to defend themselves with deadly force and does not require a retreat in the face of danger.
Asked Tuesday if that law needs change, Republican Gov. Rick Scott said "it's always positive to go back and think about existing laws."
During the town hall meeting in Sanford, Florida Rep. Geraldine Thompson promised the law's repeal would be a top priority for the state legislature's black caucus.
"If vigilante justice becomes the norm, will visitors feel comfortable coming to our state?" she said.
An online petition urging local authorities to prosecute Zimmerman had drawn more than 700,000 signatures at website Change.org as of early Wednesday.
About 50 defense attorneys and protesters filled the lobby in the governor's office Tuesday to deliver a letter seeking an independent investigation and a task force to study racial profiling.
They applauded when Scott came out of his office to talk to them. "I will make sure justice prevails," Scott said.
"I'm very comfortable that (state law enforcement) is going to do the right thing.
They're not going to let somebody do something wrong and get away with it."
Anderson reported from Fort Lauderdale, Fla. Associated Press writers Brendan Farrington and Brent Kallestad contributed from Tallahassee, Fla.
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