The accused in the shooting death of 17-year-old Trayvon Martin was calm and quiet as he appeared before a judge on Thursday, his first time in court since being charged with second-degree murder on Wednesday.

George Zimmerman's arrest is the latest plot point in an explosive seven-week narrative following the unarmed Florida teen's murder. The Feb. 26 shooting triggered a fiery national debate on the right to self-defence and a controversial Florida law.

The magistrate set May 29 as the next court date for the 28-year-old neighbourhood watch volunteer. His lawyer said he will plead not guilty and is hoping to get bail.

Legal experts say it will be difficult to obtain a second-degree murder conviction in the teenager's death, as lawyers will have to prove Zimmerman went after Martin on purpose as opposed to shooting him in self-defence.

Zimmerman's charge followed a lengthy public campaign urging police to make an arrest in the shooting. The law in Florida allows use of lethal force in cases of self-defence.

The accused turned himself in shortly after special prosecutor Angela Corey announced the plans to charge him Wednesday afternoon.

His lawyer, who took up the case after Zimmerman's previous lawyers stepped down, said his client was worried about getting a fair trial amidst the case's intense media hype.

"He is concerned about getting a fair trial and a fair presentation," Mark O'Mara said Thursday on the "Today" show. "He is a client who has a lot of hatred focused on him. I'm hoping the hatred settles down ... he has the right to his own safety and the case being tried before a judge and jury."

"He wants to be out (of jail) to be able to help with his defence, but overall he is doing ok," he said.

Martin's mother Sybrina Fulton was also on the "Today" show on Thursday, and appeared to say she believed the shooting was an accident.

"I believe that it just got out of control and he couldn't turn the clock back," she said.

Later in the day, however, she told TV host Nancy Grace that the "accident" she was referring to was her son coming into contact with Zimmerman in the first place, not the shooting.

Fulton has been campaigning for several weeks for Zimmerman's arrest and prosecution, and said Thursday that she would like Zimmerman to give her an apology.

If convicted, Zimmerman could be imprisoned for life. If he had been charged with manslaughter, a less serious offence that covers reckless or negligent killings, the prison sentence would have been closer to 15 years.

To prove murder, prosecutors must prove Zimmerman's shooting was motivated by hatred or ill will.

CTV legal expert Steven Skurka says Zimmerman is expected to stick with his self-defence explanation, but criticized the Florida law for opening the door to vigilante justice.

"There's no duty to retreat," he told CTV News Channel on Thursday. "That's why there's been this rapid increase in ‘justifiable' homicides."

The prosecution's best hope at getting a conviction, suggested Skurka, will be proving that Zimmerman engaged Martin even after a dispatcher warned him not to before the shooting.

"As neighbourhood watch, he wasn't supposed to carry a gun," said Skurka. "The kid that he shot was carrying Skittles and iced tea."

With files from The Associated Press