Man accused of stabbing Tampa bus driver to death is mentally ill, defense attorneys say

TAMPA, Fla. - After nearly three years the murder trial of Justin McGriff began Wednesday.

McGriff is accused of stabbing HART bus driver Thomas Dunn to death in May of 2019. 

The entire incident was caught on surveillance cameras inside the bus. Prosecutors played the grisly video for jurors during opening statements.  

In the video, McGriff can be seen walking from his seat in the back of the bus with a knife in his hand. He waits behind Dunn for several moments, tells him "God bless you" and when Dunn replies "Thanks. God bless you too", McGriff plunges a knife into his throat.

The bus was filled with horrified passengers, many of whom testified on the first day of McGriff’s murder trial.

McGriff’s defense team isn’t denying that he attacked and killed Dunn at random, but say mental illness is to blame.

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"One of the other interesting things about mental illness, sometimes it does truly reveal itself in isolation. This isolated act is tragic and terrible, horrific, and atrocious as it is, the most dramatic symptom that we have... this symptom just happens to be a vicious crime," said defense attorney Jamie Kane in opening statements.

Prosecutor Ronald Gale, however, contends McGriff was fully aware of what he did that day, calling to the stand several witnesses who testified McGriff had attempted to flee and to change his appearance after the slaying in order to avoid being recognized as the murderer.

"I do anticipate at this trial that you will hear from an expert from the state who will opine to you that in fact Justin McGriff was not insane at the time of the offense," stated Gale.

The State Attorney’s Office initially sought the death penalty in McGriff’s murder trial but later in 2019, McGriff was found incompetent to stand trial and sent to a state hospital for treatment.

The State Attorney’s Office later determined they would not seek the death penalty. Now, if convicted, McGriff faces life in prison.