The jury foreman in the state murder trial of former North Charleston, South Carolina, police officer Michael Slager described the climate in the jury room as "passionate, emotional" and sometimes "heated" before a mistrial was eventually declared.
"We are a group of 12 people who came from different backgrounds, trying to come up with one decision. And that just didn't happen," jury foreman Dorsey Montgomery II told ABC News.
Slager, who is white, was accused of killing Walter Scott, an unarmed black man, at a traffic stop on April 4, 2015, when Slager was a North Charleston Police Department officer. Witness video that surfaced shortly afterward appeared to show the moment Slager fatally shot Scott as he ran away. The video garnered national attention, propelling Slager into the spotlight. Slager was fired from the force after the shooting, according to The Associated Press.
The mistrial in the state case was declared Dec. 5 after the jury members said they were unable to come to a unanimous decision.
Slager had pleaded not guilty to murder. But as the trial concluded last week, the jury was allowed to consider a voluntary manslaughter charge as well. The voluntary manslaughter charge was requested by the prosecution, and the judge allowed it, based on testimony given during the trial.
Montgomery said when the jury first received the initial charge of murder, the jurors decided that wasn't something that "Mr. Slager did. He did do something, but based on the law and the clauses in the law, he didn’t commit murder based on what we saw. Because there was nothing malicious there."
Montgomery said, with the manslaughter charge, the jurors "had a lot of questions."
"We perceive a lot of things, we can read books, we can watch 'CSI,' all these different law shows," he said, "But we don’t have a good understanding of the law."
The jurors sent notes to the judge asking for clarifications as they deliberated.
Montgomery said the final vote breakdown was 10-2 in favor of voluntary manslaughter.
Of those two jurors, Montgomery said, "I respect their opinions, I respect what they decided to do. That’s why we had a mistrial."
"It could have went a whole other way," he continued. "They respect my views, I respect their views. I don't look at them any differently, I don't condemn them for not getting on board with me, but that’s just their take on it, and I respect them even more for not being easily swayed.
"And the two individuals were not willing to compromise or look at any more evidence at that point in time so it was just best for us to end it at that time," he explained.
He said on Friday the mood was "extremely intense."
There were five jurors who had already made a decision, he said, and five to six people "who hadn’t made a decision. But that one juror had already made a decision saying that he was not willing to compromise at all."
"I got emotional, other jurors got emotional," Montgomery said. In the end, they couldn't come to a decision.
Montgomery -- who called serving on the jury a badge of honor -- told ABC News that someone put a note on his door two weeks after the case started that read, "Make sure you do the right thing." "I don’t get intimidated very easily," he said. "Whoever did it, I appreciate you, thank you. ... I believe I did what you requested for me to do."
In the wake of the mistrial, Solicitor Scarlett Wilson said in a statement, "We will try Michael Slager again."
Defense attorney Andy Savage said an "honest search for the truth in any courtroom in America, one appropriately isolated from intense political pressure, should produce an acquittal in Mr. Slager's case."
Slager also faces a federal trial, which is scheduled for next year.
ABC News' Will Gretsky contributed to this report.