After deliberating for more than 16 hours, a jury of six women on Saturday evening found George Zimmerman not guilty in the shooting death of Trayvon Martin, an unarmed 17-year-old in Sanford, Fla.

Zimmerman had pleaded not guilty to charges of second-degree murder with an affirmative defense, claiming he had shot Martin to save his own life after being attacked by the teen on Feb. 26, 2012. The trial, televised nationally on cable networks and streamed live across the Internet on various sites, kept the country captivated awaiting a verdict on the tragic events that took place that rainy night.

Following four weeks of testimony, more than a dozen witnesses and a host of controversy, Zimmerman walked out of court a free man.

The case first drew national attention during the 44 days the Sanford Police Department took to decide that Zimmerman should be arrested and charged with murder. During that tense period, protests were held across the country calling for Zimmerman's arrest. Those protests were buttressed by the controversy's strong presence across the Internet, with hashtags like #JusticeForTrayvon becoming mainstays on Twitter . Celebrities including LeBron James and his Miami Heat teammates and Jamie Foxx were photographed wearing hooded sweatshirts like Martin had been wearing the night he died.

That night, Martin was walking back to the home of his father's fiancee from a local 7-Eleven convenience store after purchasing a can of iced tea and a bag of Skittles. He was spotted by Zimmerman, a neighborhood watch volunteer, who thought Martin looked suspicious because of what he described as an unnaturally slow and meandering gait. Zimmerman called the police and proceeded to follow the teen through the Retreat at Twin Lakes, the gated community where Zimmerman lived and where Martin had been staying. A confrontation ensued, Zimmerman shot Martin, Martin died, and six weeks later, Zimmerman was arrested and charged with second-degree murder.

On March 16, 2012, police released audio of the 911 calls made by Twin Lakes residents who were witness to the altercation between Martin and Zimmerman occurring near their homes. In one chilling call, a voice can be heard screaming for help in the background. The wailing ends as the loud crack of a gun shot rings out. Those screams and the question of who was making them would become pivotal for both the prosecution and the defense, with the implication being that the person screaming was the one being attacked.

As attention around the case mounted before the trial, details emerged about the teenager and the man involved in the fatal confrontation.

It turned out this wasn't Zimmerman's first run-in with the law. He had previously been accused of domestic violence by a former girlfriend , and he had also previously been arrested for assaulting a police officer . More controversially, in July 2012, an evidence dump related to the investigation of Martin's death revealed that a younger female cousin of Zimmerman's had accused him of nearly two decades of sexual molestation and assault . In addition, she had accused members of Zimmerman's family, including his Peruvian-born mother, of being proudly racist against African Americans, and recalled a number of examples of perceived bigotry.

The national focus on the case also brought into question, for some, the character and life history of Trayvon Martin. As time passed, websites like The Daily Caller found Martin's posthumously scrubbed Twitter page , which featured the teen at times tweeting profanities and showing off fake gold teeth. To some, these behaviors, along with the hoodie Martin wore the night he was killed, were an indication that he was something other than an innocent teenage boy who was shot while walking home from the store. To others, the attention paid to Martin's tattoos, gold teeth and hoodie were symptomatic of the same kind of stereotyping and profiling that led to Zimmerman's assumption that the teen was "up to no good."

While much of this background information proved inadmissible at trial, the characterizations of the two men helped drive an often racially charged polarization on the issue at the heart of the case -- whether the killing of Trayvon Martin was self-defense or murder.

The prosecution argued that Zimmerman had profiled Martin , deeming him "suspicious," as indicated by Zimmerman's description of the teen to the non-emergency hotline he called for police assistance. The prosecution said that he then stalked Martin, initiating an unnecessary confrontation that led to his shooting the 17-year-old in the chest at point-blank range.

The defense maintained that Zimmerman was just walking back to his car when Martin confronted him, punching him in his face and knocking him to the ground. According to the defense, Martin then mounted Zimmerman and smashed his head into the concrete pavement multiple times, forcing the older man to shoot the teen in order to save his own life.

Testimony at the trial was, at times, contentious. Defense attorney Don West aggressively questioned Rachel Jeantel , the friend to whom Martin was talking on the phone just before he was killed. Jeantel, who speaks English as a second language, kept her answers tersely short and stuck to her understanding of what had transpired that night, despite the defense's attempts to undermine her account. Her perceived lack of polish on the stand, though, thrust the teenager into a national conversation about whether she had hurt or helped the state's case .

The testimony of Dr. Shipping Bao, the medical examiner who performed the autopsy on Martin, was also highly contested. Bao often clashed with the defense as he repeatedly made sure that everyone in the courtroom understood the difference between what he saw as facts and what he considered opinions related to the case.

Both the prosecution and the defense went to great lengths to show who was screaming for help in the background of that 911 call. The prosecution called Trayvon Martin's mother, Sybrina Fulton, and his brother, Jahvaris Fulton, who testified that it was Martin. The defense called George Zimmerman's mother, father and a host of friends to testify that it was Zimmerman screaming.

Ultimately, there are only two people who ever knew for sure who was screaming for his life that fatal night. One of them is dead, and the other has been acquitted in his killing. And with that acquittal, this chapter of the Trayvon Martin case, one that has captivated and divided a country for almost 17 months, has been brought to a close.