Benjamin Gerard Hawkins is scheduled to testify Thursday afternoon in his involuntary manslaughter trial in the July 2011 death of 38-year-old John Massie.
Hawkins is black and from Gainesville, Fla. Massie was white and from Roy, Utah.
Both were visiting Las Vegas when they encountered each other in a restroom at O'Shea's Casino.
Hawkins told police he was defending himself when he punched Massie following derogatory comments about his race.
Silent security video shows the two men a few feet apart before Hawkins turns and throws the punch.
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