George Zimmerman celebrates with his parents Robert Zimmerman Sr. and Gladys Zimmerman celebrate following his not guilty verdict in Seminole circuit court in Sanford, Fla. Saturday, July 13, 2013. Zimmerman was found not guilty for second-degree murder for the 2012 shooting death of Trayvon Martin. (23723)
George Zimmerman celebrates with his parents Robert Zimmerman Sr. and Gladys Zimmerman celebrate following his not guilty verdict in Seminole circuit court in Sanford, Fla. Saturday, July 13, 2013. Zimmerman […] Credit: Gary W. Green

SANFORD, Fla. — George Zimmerman never denied shooting Trayvon Martin, saying he did so in self defense. Late Saturday night, a Florida jury found him not guilty in the teenager’s death.

The verdict caps a case that has inflamed passions for well over a year, much of it focused on race and gun rights.

The six jurors—all of them women—deliberated for 16½ hours total, including 13 on Saturday alone, before delivering their verdict. Five of the women are white, one is a minority.

None of them wanted to speak to the media after the verdict, court spokeswoman Michelle Kennedy tweeted.

When he learned his fate, a quiet Zimmerman had little visible reaction. He turned and shook the hand of one of his attorneys before sitting back down, only openly smiling after court was adjourned. His parents, Robert and Gladys Zimmerman, were seated nearby, but Martin’s parents were not in the courtroom.

Robert Zimmerman Jr. said there’s still plenty of fear, and his brother George “is going to be looking around his shoulder for the rest of his life.” But there’s great relief as well.

“Now the jury has spoken, and we are exonerated as a family,” he told CNN’s Piers Morgan late Saturday. “And more importantly, George is exonerated.”

Trayvon Martin’s father, Tracy Martin, took to Twitter to thank those who have supported his family and vowed they will continue to fight.

“Even though I am broken hearted my faith is unshattered I WILL ALWAYS LOVE MY BABY TRAY,” he tweeted.

The jury had three choices: to find Zimmerman guilty of second-degree murder; to find him guilty of the lesser charge of manslaughter; or to find him not guilty.

Earlier in the day, jurors asked the court for clarification on its instructions regarding manslaughter. Such a query couldn’t even have been posed a few days ago: Judge Debra Nelson ruled Thursday, over the defense’s vehement objection, to include manslaughter as an option for jurors, in addition to a second-degree murder charge.

To convict Zimmerman of manslaughter, the jurors would have had to believe that he “intentionally committed an act or acts that caused the death of Trayvon Martin.” That charge could have carried a sentence of up to 30 years in prison, though the jury was not told of that possible sentence.

For second-degree murder, the jurors would have had to believe that Martin’s unlawful killing was “done from ill will, hatred, spite or an evil intent” and would be “of such a nature that the act itself indicates an indifference to human life.”

Ultimately, they believed neither. And that means Zimmerman can walk free.

NAACP president ‘outraged and heartbroken’

Scores who had gathered outside the Sanford, Florida, courtroom hoping for a guilty verdict reacted in disbelief after word of the decision trickled through the crowd. Hours earlier, they had given speeches, singing songs and chanting, “We want justice.” Some appeared angry, others appeared sad.

Zimmerman supporters also rallied in the courtyard during the day, holding signs saying “Self-defense is a basic human right,” “Not enough evidence,” and plainly “Not guilty.” They had an entirely different view of the case: that Zimmerman had been wrongly implicated, that he’d just done what he could to save his life.

Florida State Attorney Angela Corey defended the second-degree murder charge that was filed against Zimmerman, telling reporters late Saturday that the allegations “fit the bill” for the charge.

“We believe that we brought out the truth on behalf of Trayvon Martin,” Corey told reporters shortly after the verdict was announced.

One of her prosecutors, Bernie de la Rionda, expressed disappointment with the jury’s decision, but acceptance as well.

“It’s not perfect, but it’s the best of the world,” he said of the jury system. “And we respect the jury’s verdict.”

The response from NAACP President Benjamin Todd Jealous struck a far different tone.

“We are outraged and heartbroken over today’s verdict,” Jealous said in a statement, vowing to pursue civil rights charges in the case. “We stand with Trayvon’s family, and we are called to act.”

Don West called the prosecution of his client “disgraceful,” adding, “I’m thrilled the jury kept this tragedy from becoming a travesty.”

“But it makes me sad that it took this long, under these circumstances, to finally get justice,” he added.

His colleague, Mark O’Mara, struck a different tone, saying he was “ecstatic” with the verdict. He made a point to compliment local law enforcement authorities and, especially, the jury and all the time and effort jurors put into the process.

“They listened, they took notes, they were as engaged as anyone else in the process,” O’Mara said. “And it made for the type of verdict that we had to have.”

The fateful night

The story started the night of February 26, 2012, as Martin, 17, walked back to his father’s fiancee’s house through the rain from a Sanford convenience store, where he’d bought Skittles and a drink.

Zimmerman, a neighborhood watch volunteer, spotted him and called police. A 911 dispatcher told Zimmerman that officers were on the way and not to follow the allegedly suspicious person.

Nonetheless, Zimmerman got out of his car, later telling police he just wanted to get a definitive address to relay to authorities.

Sometime after that, Zimmerman and Martin got into a physical altercation. Some neighbors took notice: On one 911 call, anguished cries for help can be heard.

Who was yelling? Martin’s mother testified she’s “absolutely” sure it was her son; Zimmerman’s parents said, with as much conviction, that it was their own child.

There are also disputes about who was the aggressor, about whether or not Martin may have seen or reached for Zimmerman’s gun, about whether Zimmerman should have had more injuries if he was pummeled, as he claims.

And some accused Zimmerman—who identifies himself as Hispanic—of racially profiling the Black teenager, a claim the defense camp flatly denied.

The prosecution never accused the defendant of being racist. But they did argue that he wrongly and spitefully prejudged Martin as one of those “f*ing punks,” as he’s heard saying under his breath in his call to police, who had pulled off crimes in his neighborhood.

“The defendant didn’t shoot Trayvon Martin because he had to,” Assistant State Attorney John Guy said. “He shot him because he wanted to. That’s the bottom line.”

Yet O’Mara had his own simple explanation for Zimmerman’s action: he defended himself.

The defense contended that Martin jumped out of some bushes and pounced on their client, as he was walking back toward his car that night, then punched him and slammed his head repeatedly into the concrete sidewalk.

“Do not give anybody the benefit of the doubt,” O’Mara urged the jury, “except for George Zimmerman.”

What’s next for Zimmerman, the case?

Before the jury’s decision was announced, civil rights leaders called for calm. So did authorities, who also made contingency plans in anticipation of possible unrest after the verdict.

But in the immediate aftermath, there were no indications around Florida or elsewhere of any violence.

That said, there was movement on other fronts.

The NAACP announced that it is calling on the Justice Department to file civil rights charges against Zimmerman, urging the public to sign a petition to support this effort.

“The most fundamental of civil rights—the right to life—was violated the night George Zimmerman stalked and then took the life of Trayvon Martin,” the advocacy group said in a statement.

Asked about the trial verdict and the status of a separate federal investigation, a Justice Department official told CNN’s Carol Cratty late Saturday night that the department “continues to evaluate the evidence generated during the federal investigation, as well as the evidence and testimony from the state trial.”

As to Zimmerman himself, O’Mara said he “has to be very cautious and protective of his safety because there is still a fringe element who have said, at least in tweets and everything else, that they want revenge—that they will not listen to a verdict of not guilty.”

The lawyer added: “I’m sure that if he could wave his magic wand, he would just sort of get his life back.”

HLN’s Grace Wong, Graham Winch, Amanda Sloane, Jonathan Anker and Anna Lanfreschi and CNN’s Mariano Castillo, Michael Pearson, Faith Karimi, Chelsea J. Carter, John Couwels and Mayra Cuevas contributed to this report.

Greg Botelho | CNN