Dunn has testified he described the music to his fiancee as "rap crap."
In the parking lot, as the music blared, "his blood started to boil; he didn't like the music that was coming out of the car next to him; he got angrier and angrier," Wolfson said.
Dunn rolled down his window and asked the youths to turn it down, which they did, but then turned it back up, Wolfson said.
"He got angry at the fact that a 17-year-old kid decided not to listen to him," she said, adding that Dunn then pulled a 9 mm gun out of his glove box and shot "systematically and methodically" at the SUV. "Nobody denied that Jordan was talking back. But this defendant took it upon himself to silence Jordan Davis forever."
Dunn testified Tuesday that he saw Davis reach down and pick something up, and that he saw about "4 inches of a barrel" from a 12- or 20-gauge shotgun above the window.
'You're not going to kill me'
He muttered aloud to himself, " 'You're not going to kill me, you son of a bitch,' " as he opened the glove compartment, grabbed his pistol, dropped the holster at his feet, chambered a round and began firing, he said.
Nine of the 10 rounds hit the car, and three of them struck Davis, one of them cutting through his liver, his lung and his aorta.
Wolfson rejected Dunn's assertion he had been trying to de-escalate the situation and he feared for his life.
Strolla, the defense attorney, noted that no witnesses had accused Dunn of using any hate words and testified that his client had just come from a wedding, where his ex-wife said he had appeared to be in a good mood.
Strolla noted that the SUV departed the gas station after the shooting and was gone for three minutes before it returned, enough time for the youths to have dumped a gun.
Detectives did not search the area for days after the shooting, he said.
Strolla cited testimony from another passenger in the car with Davis who acknowledged he may not have heard all the conversation between the two men.
'You have reasonable doubt'
Witnesses testified that child locks on the SUV were engaged, and that Davis -- who was seated in the rear -- could not have gotten out of the back seat to threaten Dunn. But Strolla said the teen could simply have opened the door by putting his hand out the window, which was open.
"You have lack of evidence, conflicts of evidence and reasonable doubt," he told the jurors.
On rebuttal, Assistant State Attorney John Guy appealed to the jurors' "common sense."
"That defendant didn't shoot into a car full of kids to save his life," he said. "He shot into it to preserve his pride. Period. That's why we're here."
Though Davis may have had a big mouth, he had no weapon, Guy said. Though he acknowledged minor inconsistencies in witness accounts, he said that was to be expected. "It's not like television," he said. "In real life, there are inconsistencies."
The court has decided not to release the identifications of the jurors, fearing they could be the subject of threats, but a document obtained by CNN affiliate WTLV-TV in Jacksonville showed the makeup of the jury.
It has four white females, two black females, four white males, an Asian female and a Hispanic male, plus four alternates.