NEW: Trayvon Martin's mother says she believes his death was an accident George Zimmerman is "stressed" and "tired," his attorney says Attorney Mark O'Mara says Zimmerman is at risk Also, if a judge requires Zimmerman to remain in the area if he is granted bail, that will be difficult, O'Mara added. "I think nobody would deny the fact if George Zimmerman is walking down the street today, he would be at risk," he explained. However, O'Mara said Thursday he is "truly hoping that there will be a receding of the frustrations or anger now that the process is moving forward." Zimmerman's attorney no stranger to high-profile cases Zimmerman, 28, who had been in hiding, turned himself in Wednesday after authorities said he would be charged in the case. He faces a second-degree murder charge in the February 26 shooting death of 17-year-old Trayvon Martin. He will make an initial court appearance Thursday before Judge Mark Herr. Blog: Updates on charges and arrest as they unfolded The development marks a turning point in a case that triggered a nationwide debate about race in America and about Florida's "stand your ground" law -- which allows people to use deadly force anywhere they feel a reasonable threat of death or serious injury. However, the attorney said Thursday he does not share those concerns. "Florida has a very good process in place to make sure we get a fair and impartial jury," he told CNN. Other high-profile cases have been able to do so. I trust that the system, the judge, the prosecutor and I will be able to, should the need arise, to get ourselves a fair and impartial jury to hear the case. It may not be in Seminole County. He said that while he isn't sure the bond request will be heard Thursday, he needs Zimmerman out of jail to help assist in his defense. Martin's family, meanwhile, expressed satisfaction that Zimmerman has been charged and is in custody. "We simply wanted an arrest; we wanted nothing more, nothing less," the teen's mother, Sybrina Fulton, said Wednesday. Natalie Jackson, an attorney for Martin's family, said Thursday the family has only asked "for justice to apply equally for all. If a judge decides (Zimmerman) has a right to bail, then that's the system, and we'll respect the system. On Thursday, Fulton told NBC's "Today" she believes her son's death was an accident. "I believe that it just got out of control, and he couldn't turn the clock back," she said. I would ask (Zimmerman), did he know that that was a minor, that he was a teenager and that he did not have a weapon? ... I understand that his family is hurting, but think about our family that lost our teenage son. The special prosecutor assigned to the case announced the charge against Zimmerman Wednesday -- 46 days after the shooting. During that time, the calls for "Justice for Trayvon" had grown louder and louder, with Martin's supporters taking to the streets in cities across the nation and on the Internet. Prosecutor Angela Corey said whether the case is decided by a judge or jury, "I can assure they will only get the relevant, admissible evidence on which they can then base their decisions." "I did think that was certainly the highest charge I ever thought they would charge," O'Mara said. It seemed like it might be manslaughter, but ... I don't want to prejudge something when I know nothing about the facts. I would rather that come out the way it's supposed to. Jackson said Thursday she believes the charge was appropriate. "It's actually a very brave charge of Angela Corey and really shows that she conducted an independent, impartial and fair investigation in this case," the attorney said. She could have easily charged this as a manslaughter to try to appease everyone. She didn't. She did what prosecutors do. She charged it to the hilt. Jurors, however, will have several options under Florida law, including aggravating factors such as Martin's status as a child, since he was under 18, or other variations of manslaughter, Jackson said. Charge amid conflicting allegations What is known is that Martin, wearing a hoodie, left his father's fiancee's home in Sanford to get a snack at a nearby convenience store that Sunday evening in February. Sanford police initially questioned Zimmerman and released him without charges. From there, the case has evolved into conflicting allegations from Zimmerman's supporters, Martin's family and authorities. Martin's family and supporters say Zimmerman, who is Hispanic, racially profiled the teen, who was African-American, and called 911 to report a suspicious person in the neighborhood. A recording of the 911 call includes a police dispatcher asking Zimmerman, "Are you following him?" "Yeah," Zimmerman replied. "OK, we don't need you to do that," the dispatcher said. The recording also captured someone pleading for help. Zimmerman's family says it was him yelling for help; Martin's relatives have said they are certain the voice is that of the teen. They told reporters Tuesday that they had lost contact with their client and could no longer represent him. He is a well-known criminal defense attorney who is no stranger to high-profile cases and TV cameras. O'Mara said Thursday he spoke to Zimmerman by telephone several times during the day Wednesday and spent about an hour with his client Wednesday night. He is stressed. He's tired. He's been through a lot with the way this case has been handled to date," he said of Zimmerman. I'm just hoping that his mental health stays well and we can move forward with getting the case figured out. The case has drawn comments from President Barack Obama -- a father of two girls, who said, "If I had a son, he'd look like Trayvon" -- and led to protest marches in cities and campuses across the country. At one point, the New Black Panther Party offered a $10,000 bounty for Zimmerman's capture, despite vehement opposition from, among others, Martin's family. He stopped reporting to work at a mortgage risk management firm after the shooting. O'Mara told CNN and sister network HLN on Thursday he expects it will take at least six months, and possibly as long as a year, before the trial is held. But, he said, that's speculation, since he hasn't had an opportunity to review evidence in the case yet. Meanwhile, Attorney General Eric Holder pledged Wednesday that the Justice Department, which is running a concurrent investigation launched three weeks ago, will "conduct a thorough and independent review of the evidence." Zahra Umansky, an attorney who represented Zimmerman on 2005 charges of assaulting an officer and resisting arrest after an incident in a local bar -- charges which were later dismissed -- recalled he was actively involved in his defense, more so than other youths at that age might be. "He was very concerned," she said. She characterized Zimmerman as having a tendency to not accept what he's told at face value. He wants to take things and find out what's going on. ... He's curious," she said. At a barber shop in west Sanford, an area that has served as a gathering point for Martin protesters, Demetrius Hastings watched a live broadcast of Corey's announcement of the charge against Zimmerman.