TAMPA (WFLA) – Attorneys went back and forth in court Monday over what witnesses actually saw after police said a passenger stabbed a city bus driver to death in Tampa. 

A Hillsborough County judge denied bond for accused murderer Justin McGriff.

McGriff, 35, was wearing an anti-suicide gown during the first appearance hearing. His attorney argued that some witnesses weren’t able to identify McGriff for sure as the person responsible for the crime. 

“In reading through the report, even family members of the defendant are unable to identify him in footage allegedly obtained from the bus,” said McGriff’s attorney. 

A state prosecutor pushed back and argued how others pointed out McGriff as the killer. 

“The defendant literally cut the throat of the bus driver without prior warning,” said a state prosecutor. 

The judge agreed the evidence was clear and said, “I read down the line and it does state that two witnesses identified the defendant with certainty as the person in the video.”

Tampa police said McGriff stabbed the driver, identified as Thomas Dunn, to death Saturday afternoon while the bus was traveling down Nebraska Avenue near Linebaugh Avenue.  

“As the bus operator’s last act as a HART employee and the bus operator’s last act on this earth, after being struck, was successfully navigating the bus to the side of the road and stopping the bus and saving further injuries,” said HART CEO Benjamin Limmer. 

Dunn brought up safety concerns in a HART meeting back in December where he’s on video saying a woman assaulted him and nothing was done after he followed protocol. 

HART leaders would not say for sure whether the route was flagged due to issues in the past. 

They did reveal it is one of the heavily traveled routes, which goes through the USF area and downtown Tampa. Many are now wondering whether a glass enclosure is what drivers need.

“In the past, some of the operators did not; they felt a little confined by that. That they were boxed in and they didn’t feel comfortable in it almost created an additional hazard,” said HART Director of Safety Collin Mulloy. “But in light of this horrible tragedy we need to take a deeper look and have a 360 view of how we really make sure that we keep that safety and security.”

Mayor Jane Castor, at the scene Saturday afternoon, also sits on the board for HART, and says while this was an isolated incident, safety changes will be discussed.

“What we have to do is prepare our drivers, our operators, as best as the organization can to anticipate any incidents that may occur,” she said..

Mulloy said camera systems in HART vehicles recently had a $1.3 million overhaul. He also said a 24-hour control center is in direct communication with police and fire in the event of emergencies. 

HART leaders said they’re speaking with other agencies across the state to consider the best safety measures for the agency to implement in Hillsborough County. 

McGriff has a pre-trial hearing set for Friday.