(CNN) -- The attorney representing George Zimmerman, who is charged with killing an unarmed, black teen, is no stranger to high-profile cases and TV cameras.
Mark O'Mara gained notoriety in Florida for defending a man who killed a woman during a high-speed chase and then later as a legal commentator during the Casey Anthony murder trial.
"Mark knows how to handle the media. But he's also not a media hog," said CNN legal analyst Mark Najame, who has gone up against O'Mara in the courtroom. "He's going to go out and say and do what's appropriate on behalf of his client."
O'Mara is expected to make his first court appearance Thursday with Zimmerman, who faces a second-degree murder charge in the February 26 shooting death of 17-year-old Trayvon Martin in the suburban Orlando community of Sanford.
O'Mara told CNN on Thursday that while he is concerned about Zimmerman's safety, he needs his client out of custody "to assist me in going over all the evidence and preparing our defense."
He said he wasn't sure whether a bond request would be heard Thursday and noted he has only had 16 hours to prepare for the hearing.
O'Mara, who has spent nearly 30 years practicing criminal and family law in central Florida, replaces Craig Sonner and Hal Uhrig as Zimmerman's attorneys. They told reporters Tuesday that they had lost contact with their client and no longer represent him.
The same day, O'Mara questioned the attorneys' statements -- in his role as a legal analyst on Central Florida's WKMG Channel 6.
"I think that was a little problematic," he said. "You're not supposed to talk about a client's case, for the most part at all, and yet they answered dozens of questions."
Asked about Uhrig's statement that Zimmerman may have "post-traumatic stress," O'Mara said Thursday, "A diagnosis like that should be made by a professional psychologist or psychiatrist. I'm not going to make a diagnosis like that.
"He is stressed. He's tired. He's been through a lot with the way this case has been handled to date," O'Mara said of his client. "I'm just hoping his mental health stays well, and we can move forward with getting the case figured out."
On Wednesday, O'Mara told reporters that Zimmerman's family contacted him after referrals from other lawyers.
Hours later, Zimmerman surrendered to authorities, and O'Mara stepped in front of a sea of television cameras.
"We voluntarily surrendered him to law enforcement, with the realization that the charges were going to come, and he did that, again, voluntarily, and we're trying to work out the best way to keep this as calm as we can," he said.
Zimmerman has said he killed Martin in self-defense after the teen punched him and slammed his head on the sidewalk, according to Sanford police.
Martin's family says Zimmerman, who is Hispanic, racially profiled the youth, who was black, and ignored a police dispatcher's directive not to follow him.
Last month, O'Mara told WKMG that the shooting could be legally justified under Florida's "Stand Your Ground" law, which allows people to use deadly force anywhere they feel a reasonable threat of death or serious injury.
"Other people call it the license to murder statue because it doesn't require actions to avoid the confrontation," he said.
"If you can present evidence or at least your own testimony that (you) felt in fear that he was going to commit great bodily injury or death, that is what kicks in the statutory protection that you're allowed to respond with deadly force."
In 2004, O'Mara defended Shamir Suber, who was charged with second-degree murder for plowing into the back of a car and killing 20-year-old Sara Phillips while trying to evade police during a high-speed chase.
Suber was convicted of the lesser charge of DUI manslaughter in the death of the University of Central Florida nursing student, a case that underscored the risks of high-speed police pursuits.
O'Mara's website says before becoming a criminal defense attorney, he worked as a criminal prosecutor. "He knows how to defend you because he knows how they will prosecute you," it said.
Zimmerman was alone Wednesday when he turned himself in to the Florida Department of Law Enforcement's office in Jacksonville, said department spokeswoman Joyce Dawley.
"There's a lot of issues and there's a lot of emotions, and we need to calm this down," O'Mara said. "It needs to be tried in a courtroom, which is the only place it's supposed to be tried, and that's what I'm going to try help get done."
O'Mara graduated from Florida State University College of Law in 1982 and passed the Florida bar that same year.