The Georgia Supreme Court overturned the conviction of a man who was found guilty of intentionally running over and killing a Douglas County grandmother.

The court unanimously ruled Thursday that a trial court excluded a key witness' testimony that may have affected the jury's guilty verdict against Dewey Calhoun Green, who was 24 years old at the time. The court found that "the trial court abused its discretion in excluding (an accident reconstructionist)'s entire testimony from trial."

Green was convicted of malice murder, three counts of felony murder and three counts of aggravated assault in August 2015, netting him a life sentence without parole, AJC.com previously reported.

It’s unclear whether prosecutors will retry the case. AJC.com has reached out to the Douglas County District Attorney’s Office to try to find out.

RELATED: Life without parole for man who ran over Douglas County grandmother

On June 25, 2014, 53-year-old Janice Pitts was driving her SUV south on Ga. 5 with her daughter, Iesha Davis, and 4-year-old grandson as passengers, according to evidence presented in court. Green rear-ended her SUV with his pickup truck as she was switching into a turn lane.

Pitts and Davis got out of the vehicle to examine the damage. When Pitts reached the back of her SUV, Green’s truck moved forward, pinning her between the vehicles. Davis banged on Green’s window in an effort to get him to stop his truck, but he allegedly didn’t respond.

Prosecutors said Green eventually backed up the truck, drove partly over a curb and ran over Pitts, who had fallen. Davis said she had to move out of the way to avoid the oncoming truck.

Green ended up stopping the truck on a grassy hill in front of a nearby business. A man who witnessed the incident approached Green’s truck and shifted the vehicle into park before police arrived and arrested Green.

Pitts later died from her injuries.

Janice Pitts

Credit: Channel 2 Action News

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Credit: Channel 2 Action News

The core of the case was whether Green was “conscious and voluntary” during the incident, the supreme court said. The defense claimed he suffered a seizure before or during the initial wreck, and the vehicle’s actions afterward were uncontrolled by him.

The state argued that Green had trace amounts of sedatives in his blood and had been up late the night before the accident. Prosecutors said Green intentionally drove his truck into Pitts, although his judgment was impaired.

Sean Alexander, an accident reconstructionist, was not permitted to testify during trial because the defense did not submit written reports detailing his opinions before a deadline, citing OCGA § 17-16-4 (b).

However, the supreme court said the trial court “erroneously excluded Alexander ... from testifying at trial.” The supreme court ruled that Alexander only needed to prepare a report if he planned to introduce evidence that results from “scientific tests or experiments.”

Alexander planned to testify that Green’s truck could have taken the path it did during the incident without being controlled, citing the speed and path.

He performed a roll test using another vehicle at the same location, and it idled at a similar speed and path to that of Green’s vehicle. The court said that could reasonably be defined as a “scientific test or experiment” that required disclosure in a report to prosecutors, but the rest of his testimony did not, since all other evidence he planned to use was available to prosecutors.

That evidence included photos from the scene, surveillance video of the road, witness video after the collision and various measurements.

This is a photo of the pickup truck after the incident.

Credit: Channel 2 Action News

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Credit: Channel 2 Action News

Alexander’s testimony would have supported the defense’s version of events, and the supreme court said that was significant, since the state’s evidence “rested almost entirely on the credibility of its expert witnesses and the observations of some of the witnesses at the scene.”

Of 15 witnesses, nine said they saw Green back up his vehicle in some fashion, while four said “Green’s truck pushed against Pitts’ SUV in a continuous motion,” which is plausible if the vehicle was idling, the supreme court said.

“Alexander’s testimony ... would have given weight and credence to the testimony of the witnesses who testified that Green appeared dazed and unresponsive or that he appeared to be experiencing some sort of medical event, as well as the defense’s argument that Green was not consciously controlling his truck. It would also strengthen and explain the testimony of the witnesses who did not see Green back up, but rather observed Green’s truck push against Pitts and her SUV in more of a rolling motion until finally getting past the SUV.”

Green has maintained his innocence and said he did not intend to kill Pitts.

“I understand my apologies may seem petty in comparison to anguish you have toward me, but I am not the person that police and the media have portrayed,” Green previously said. “Believe me when I say I value life and family; I wouldn’t never kill anyone on purpose.”

He shouted an expletive declaring his innocence after being convicted of murder.

“I’m not (expletive) guilty,” Green said before being led out of the courtroom by deputies.

Click here to read the supreme court's full ruling.

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