Tensing was charged with murder and voluntary manslaughter after fatally shooting Samuel DuBose during a July 2015 traffic stop. The officer testified he shot DuBose because he feared for his life after his left arm became trapped inside DuBose's moving car July 19, 2015.
Saying "there is not a likelihood of success at (a third) trial," Hamilton County prosecutor Joseph Deters said he based his decision on speaking to jurors who declined to find fault in police officers' actions.
"I truly believe in this case or I wouldn't have brought it," he told reporters. "In this case, we have jurors who will not vote to convict a police officer."
"To say that we overcharged (Tensing) is absolutely idiotic," he added.
Deters said he had spoken to DuBose's family and said they are upset with his decision.
"It was horrible," he said. "It'd be the reaction I would have if this was my brother."
The matter has been referred to the U.S. Attorney's Office for potential civil rights violations, Deters said, adding that a member of his staff has met with the feds to review evidence.
US Attorney Benjamin C. Glassman said his office will acquire and review the evidence from the state court trials to determine "whether there are possible federal civil rights offenses warranting investigation and potential prosecution."
Court proceedings in June
ended in mistrial.
A body cam video showed the deadly encounter between Tensing and DuBose -- including the moment when Tensing fatally shoots DuBose, though it is difficult to see. A bang can be heard, but the camera is shaking so much that a viewer doesn't clearly see the shooting itself.
The video eventually shows Tensing holding his gun in front of his chest after DuBose has driven away. Representatives from both sides interpreted the footage differently.
While prosecutors in June told the jury that Tensing made a tactical error when he reached his left arm inside DuBose's car and then escalated the problem by firing his weapon, Tensing's attorney argued otherwise.
Stew Mathews contended that DuBose "elected to start that car, put it into gear and take off with Ray Tensing's arm trapped inside it. I submit to you that is a threat to his life and to his well-being."
The death of DuBose, who was black, came amid other controversial police-involved shootings of black males -- including those of Tamir Rice
in Cleveland, Michael Brown
in Ferguson, Missouri and Walter Scott
in North Charleston, South Carolina.
The University of Cincinnati agreed in January 2016 to pay $4.85 million to the family of DuBose. The school also agreed to set up a memorial to DuBose on campus, invite the family to take part in meetings on police reform, issue a formal apology and provide free undergraduate education to DuBose's 12 children.