Simpson, 65, took the stand to testify about the 2007 incident in which he claimed he was trying to recover stolen sports memorabilia from his football glory days. He is currently serving a sentence of 9 to 33 years for armed robbery and kidnapping connected to the case.
Simpson appeared more animated than he had in the first two days of the hearing.
The former football star and actor, now with short graying hair and a receding hairline, spoke clearly and confidently as he recounted the events leading up to the hotel room confrontation. On that day, Simpson said he and some friends confronted two sports memorabilia dealers who were in possession of Simpson's footballs and family photos, and how he believed he had the right to take back what he claimed had been stolen from him.
"The overall advice he gave me, was you have a right to get your stuff," Simpson said.
During the trial, two co-defendants who took plea deals and testified for the prosecution, said they had guns. Simpson, however, was adamant Wednesday that he never asked anyone to bring weapons.
"There was no talk of guns at all," he told his co-counsel, Patricia Palm.
Wednesday was the third day in what's expected to be a week-long hearing in which Simpson is hoping to get a new trial, saying his attorney in that trial, Yale Galanter, did a poor job of representing him, including not properly informing him of a plea deal the prosecution was offering in the case.
A main point Simpson is trying to drive home in his testimony is that Galanter approved of Simpson's plan to get the memorabilia back. He said he spoke with Galanter extensively about what he planned to do.
Simpson testified that he and Galanter agreed to call the police if the dealers refused to give him the items.
"That's what I told everybody involved, that if they don't give it to me, I'm going to get the police in there," he said.
In 2008, Simpson was near tears as he told a judge: "I didn't mean to steal anything from anybody ... I'm sorry. I'm sorry for all of it."
There is no jury in the hearing and his fate will be determined by Clark County District Judge Linda Marie Bell.
Palm said she's not expecting any surprises during his lengthy testimony.
"We're just telling him to take the stand and tell the truth. We'll walk him through each of the claims," said Palm. "It's big, because some of these are going to come down to credibility determinations by the judge, and we don't know what Mr. Galanter is going to say."
That is the big question: what will Galanter say? He will be testifying Friday.
Simpson did win a small victory Tuesday when the judge agreed to allow him to have one hand unshackled to take notes and drink water. The other hand will still be handcuffed to his chair.
The Associated Press contributed to this report.