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Man accused in HART driver slaying found mentally incompetent

Justin McGriff will be transferred to Florida State Hospital to be treated and, if possible, made competent to stand trial.
In this image from the Hillsborough State Attorney's Office killer Justin McGriff is seen just prior to slashing the throat of HART bus driver Thomas Dunn, prosecutors say. [PHOTO COURTESY OF HILLSBOROUGH S  |  Photo courtesy of Hillsborough S]
In this image from the Hillsborough State Attorney's Office killer Justin McGriff is seen just prior to slashing the throat of HART bus driver Thomas Dunn, prosecutors say. [PHOTO COURTESY OF HILLSBOROUGH S | Photo courtesy of Hillsborough S]
Published Aug. 23, 2019

TAMPA — A man accused of slitting the throat of a public bus driver as he drove down Nebraska Avenue is not mentally competent to stand trial, a judge ruled Friday.

Circuit Judge Christopher Sabella issued the ruling after reviewing the findings of two court-appointed experts who evaluated Justin McGriff, a 36-year-old Tampa man charged with first degree murder in the May 18 slaying of Hillsborough Area Regional Transit Authority driver Thomas Dunn.

Prosecutors are seeking the death penalty.

Psychologists Jennifer Barror-Levine and Fred Farzanegan were tasked with determining whether McGriff “has sufficient present ability to consult with the defendant’s lawyer with a reasonable degree of rational understanding and whether the defendant has a rational, as well as factual, understanding of the proceedings,” according to a judge’s July order appointing them.

Sabella ordered McGriff transferred to Florida State Hospital in Chattahoochee to undergo treatment and make him competent to stand trial, if possible.

Bus driver Thomas Dunn speaks about driver safety at a Hillsborough Area Regional Transit Authority board meeting in December. Dunn, a 46-year-old U.S. Air Force veteran, was killed May 20 by passenger Justin McGriff, who slit his throat as he drove the MetroRapid bus down Nebraska Avenue, police said. [TONY MARRERO | YouTube]

According to testimony and footage and audio captured by the bus’s surveillance system, McGriff walked from the back of the bus clenching a knife in his hand and spoke briefly to Dunn as he drove south on Nebraska near Linebaugh Avenue.

“God bless you,” McGriff said

"What was that?" Dunn said.

"God bless you," he said again.

"Thank you," Dunn said. "God bless you, too."

McGriff then lunged forward, slitting Dunn’s throat, prosecutors say.

PREVIOUS COVERAGE: Slain HART driver chose busy route because he ‘loved people,’ friend says

Dunn steered the bus to the right and began to slow down as he slumped against his seat belt. McGriff moved to the door, looked back at the driver, then forced his way out. Tampa police officers arrested him a short time later after a brief foot chase.

Dunn, 46, died on the bus shortly after the attack.

Prosecutors have said the attack appears to be random. Court records show that people who knew McGriff told police he had been behaving erratically for several days before the killing.

Justin Ryan McGriff, 36, is seen in his booking photo taken on May 20. [TONY MARRERO | Tampa Police Department]


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