A man who witnessed a fatal crash on Interstate 24 that involved a Tennessee Highway Patrol trooper is shedding more light into what happened. 

Joshua Weiss was on his way back home from Nashville with his fiancee and remembers the moments before impact. 

"A trooper comes up comes up behind me and kind of gets on my tail. I know that means to get over to the right lane. I get over, he passes me," he said, "The trooper changed lanes and almost immediately you see his lights kind of come on and him kind of angle to the left and the driver side rear, I think it was a black Yukon, and it just smashed."

READ MORE | Report cites THP trooper as 'inattentive" in fatal I-24 crash

Several details surrounding the crash that killed Jim Garner, 66, remain unclear like where Trooper Clyde Reeves was going. But a report does cite Reeves as being "inattentive" in the moments leading up to the crash. 

"The trooper, no sirens, no lights, no emergency equipment whatsoever," Weiss added. 

Weiss, who is also a criminal defense attorney, said he would need more information to determine if charges are possible but says felony charges could be brought. 

"The worst possible I could see is maybe reckless homicide, which is a D felony. It could be criminally negligent homicide, which is an E felony," he said. 

As Weiss waits for more answers, he often thinks about those who are affected most: Garner's family. 

A spokesperson for THP says the investigation is ongoing and for that reason, the agency can't comment at this time. 

They do tell Channel 3 Reeves has been on paid leave since the crash. 

District Attorney Mike Taylor says his office will not pursue charges against the trooper.

"I have formally today notified the THP and the next of kin of Mr. James Garner that this office will not pursue criminal charges against Trooper Clyde Reeves relating to the fatal crash of 4-23-16 on the I-24 Nickajack bridge in Marion County," Taylor says. "The facts of this case would support a case of civil negligence but would not support a viable criminal prosecution."

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