SANFORD, Florida (CNN) -- Supporters of slain teen Trayvon Martin and his acknowledged killer continued Tuesday to battle over the significance of evidence in the case.
A Martin family attorney insisted Tuesday that the former prosecutor in the case met with the now sidelined police chief to discuss the case hours after Martin died, overruling a police detective who the family says prepared an affidavit urging that neighborhood watch captain George Zimmerman be arrested.
Meanwhile, a friend of Zimmerman's told CNN that video of the neighborhood watch volunteer in police custody does seem to show injuries consistent with Zimmerman's report that Martin slammed his head to the concrete after the two exchanged words.
FBI agents were in Sanford on Tuesday, continuing their interviews in a civil rights investigation of the case, which Martin family supporters say is a clear-cut case of racial profiling leading to an unjust killing. One of the people they met with Tuesday is Frank Taaffe, Zimmerman's neighbor and friend.
On Monday, agents interviewed Martin's girlfriend, the 16-year-old girl who, phone records show, was on the line with him shortly before the fatal confrontation, Martin family attorney Daryl Parks confirmed Tuesday.
Special prosecutor Angela Corey's investigation also continued.
Martin's family and supporters say Zimmerman, who is Hispanic, profiled Martin, who was black, as "suspicious" and ignored a police dispatcher's request that he not follow him. Martin had a bag of Skittles and an iced tea at the time of his death.
The 28-year-old neighborhood watch volunteer has said he killed the unarmed 17-year-old in self-defense, saying the teen punched him and slammed his head into a sidewalk before the shooting, according to family members and police.
Rallies nationwide have called for Zimmerman's arrest, decrying the Sanford Police Department's handling of the case.
Zimmerman's legal adviser, Craig Sonner, said on Tuesday that criminal defense lawyer Hal Uhrig would represent Zimmerman and that Sonner would serve as co-counsel if the case were to proceed. Uhrig spent more than six years with the Gainesville Police Department in Florida before graduating from law school in 1974.
In an interview with WOFL-TV in Orlando, both lawyers said they had communicated with Zimmerman only by telephone. Sonner said Zimmerman, who has not appeared publicly since the shooting, was concerned about "people who will do him harm."
On Tuesday, Martin family attorney Jasmine Rand insisted again that the former prosecutor in the case, State Attorney Norm Wolfinger, met with the now sidelined Sanford police chief on the night of the killing and overruled a police detective urging that Zimmerman be arrested.
In a letter delivered Monday to the U.S. Justice Department, the Martin family said the Sanford police detective "filed an affidavit stating that he did not find Zimmerman's statements credible in light of the circumstances and facts surrounding the shooting."
The Martin family said Sanford Police Chief Bill Lee and State Attorney Norm Wolfinger met the night of the shooting and disregarded the detective's advice, allowing Zimmerman to remain free.
ABC News has reported that the lead homicide investigator, Chris Serino, filed an affidavit pushing for charges the night of the killing, but was overruled by the state attorney's office.
Neither Sanford police nor prosecutors have confirmed the existence of such an affidavit. Sanford officials and special prosecutor Corey's office declined to comment.
On Tuesday, Rand said she had not seen a copy of the affidavit, but said she believed several news organizations had.
But Wolfinger, who stepped aside in the case last month, vehemently denied that any "such meeting or communication occurred" between him and Lee.
"I am outraged by the outright lies contained in the letter by Benjamin Crump," a Martin family attorney, Wolfinger said in a statement Monday.
"I have been encouraging those spreading the irresponsible rhetoric to stop and allow State Attorney Angela Corey to complete her work," he said. "Another falsehood distributed to the media does nothing to forward that process."
Rand said the family's legal team has multiple, credible sources who say Wolfinger and Lee met that night. She declined to elaborate.
The two sides also argued Tuesday over surveillance video showing Zimmerman in police custody after the shooting.
An enhanced copy of the video appears to show a bump, mark or injury on Zimmerman's head more clearly than does another copy of the video previously reviewed by CNN. That video had a grainy quality.
While the video does not appear to show major wounds, Taaffe, Zimmerman's neighbor and friend, said Seminole County paramedics cared for Zimmerman before they released him to police.
"That's why you don't see him like he came out of a 12-round fight like Rocky Balboa against Apollo Creed," Taaffe said.