Now, will there be violence because of the verdict?

[antiquity]

No force on heaven or earth can overturn a Non-Guilty verdict. If we've gone that far, it is immediate grounds for exercise the Second Amendment in order to enforce our Ninth Amendment right to abolish a government that has become destructive of those ends.

The Declaration of Independence is the Supreme Law of the Land, for without it, the Constitution itself has no validity.

Actually a not guilty verdict can be not overturned in a civilian court but a federal civil right violation can be used and Zimmerman can be tried again under federal law.

Rodney King verdict:

On April 29, 1992, three of the four police officers, (Koon, Wind, and Briseno) were acquitted of all charges.

On August 4, 1992 a Federal Grand Jury after hearing evidence from federal prosecutors, indicted the four officers on charges of violating King's civil rights. The four men were put on trial on February 25, 1993 in the United States District Court for the Central District of California located in downtown Los Angeles. On April 16, 1993 the trial ended with two of the police officers, (Koon and Powell) found guilty, and subsequently imprisoned. The other two officers, (Wind and Briseno) were acquitted.