The problem isn't Florida juries. The problem is this law, which makes it extremely difficult to convict someone based on their stated perception of threat, and it's what makes the law inherently dangerous to black people:

JACKSONVILLE, Fla. — In failing to acquit or convict Michael Dunn on the most significant charge — the premeditated murder of a teenager in a dispute over loud music — a jury on Saturday may have run headlong into the breadth and reach of Florida’s contentious self-defense law.

In their 30 hours of deliberation, the 12-member panel wrangled with a question that cuts to the heart of all self-defense claims: How does a juror know when using lethal force is justified, where nothing is straightforward, memories are hazy or contradictory and perception counts as much as fact?

Even as the jury agreed to convict Mr. Dunn of attempted murder, it found no consensus on murder.

In the courtroom, Mr. Dunn told the jury he shot Jordan Davis, 17, after the teenager pointed a shotgun at him from the window of a sport utility vehicle, threatened him and then got out of the truck. The two cars were parked side by side in front of a gas station convenience store.

But the prosecution said there was no shotgun: No witness saw one, the three teenagers who were in the vehicle with Mr. Davis said they did not have a shotgun, and the police never found one. While Mr. Dunn fired 10 rounds at the teenagers on Nov. 23, 2012, no one ever shot back.

Rather, the prosecution argued, Mr. Dunn shot Mr. Davis because he became enraged after the teenager disregarded his request to turn down the loud rap music blasting from the vehicle and then “mouthed off,” hurling expletives at him. He fabricated a story about the shotgun to bolster his self-defense claim, they added.

But the state failed to persuade everyone on the jury — four white men, four white women, one Hispanic man, two black women and an Asian-American woman — of their version of events. As a result, the judge was forced to declare a mistrial Saturday on the charge of first-degree murder. A new trial on that count is expected to take place later this year.

“This trial is indicative of how much of a problem Stand Your Ground laws really do create,” said Mary Anne Franks, an associate law professor at the University of Miami. “By the time you have an incident like this and ask a jury to look at the facts, it’s difficult to re-create the situation and determine the reasonableness of a defendant’s fear.”

The jury did convict Mr. Dunn, 47, on three counts of second-degree attempted murder, one for each surviving teenager in the car. Jurors agreed that Mr. Dunn was trying to kill the teenagers — not to defend himself — when he got out of his car, crouched and shot several more bullets into the truck as it drove away.

By that point, the teenagers posed no threat and there was no need to continue shooting, the jurors concluded.

For that, Mr. Dunn will serve at least 60 years in prison.

But it was the much thornier accusation of premeditated murder, as well as the lesser charges automatically included in jury instructions, among them second-degree murder and manslaughter, which tripped up a jury that, by all accounts, worked hard to try to resolve its differences.