EXCLUSIVE: Ron Shipp knew something was wrong when he met up with his pal Nicole Brown Simpson.

It was 1989 and the wife of former football star O.J. Simpson had previously called 911, telling responding police officers that her spouse was trying to physically abuse her.

Twenty-five years after the “trial of the century,” one of the nation’s most infamous investigations and trials is being examined in Investigation Discovery’s (ID) new documentary“OJ & Nicole: An American Tragedy.” 

The film features interviews with Shipp, a former Los Angeles police officer, and Simpson’s youngest sister Tanya Brown as well as never-before-seen photos, videos, and shocking diary entries and notes left by Simpson. Other friends of the couple, along with attorneys and law enforcement personnel, also participated in the true-crime special.

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Shipp played for the USC football team in 1972, and met Simpson while there. The former officer developed a decades-long friendship with the star, as well as Nicole Brown Simpson, whom O.J. married in 1985. Shipp had personal conversations with both Simpson and O.J., with each telling him things in confidence that ended up being crucial to the explosive trial.

Shipp, who previously taught domestic violence awareness, told Fox News he was stunned when saw Nicole after that 911 call. Despite her beaming smile, he claimed it was obvious she applied heavy makeup on her face. He said it was during that meeting where she came clean about her tumultuous marriage to O.J.

“First of all, I was totally in shock,” he described. “I’m like, ‘This can’t be the OK that I know.’ But I realized when she showed me the pictures and as I’m talking to her, she broke down … she was crying. I’ve never seen Nicole cry. Never. I didn’t know what to do, but I was really shocked. And then she just told me everything. Then I just said, ‘Nicole, we’ve got to get you some help. We’ve got to get you a counselor.'"

While Nicole confided in Shipp, he wasn’t prepared for the revelations that were made in her diary.

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Former friend and confidante of OJ Simpson and veteran of the LAPD Ron Shipp. (Photo by Greg Doherty/Getty Images)

“I never knew about all the writings that she did and I was actually surprised,” he admitted. “When Tanya’s reading them, it was a tearjerker for me and my wife. It’s like reliving the whole thing. I didn’t know they existed, but when you hear Nicole just pouring out her heart and what she’s feeling, it’s horrible. It’s sad that something couldn’t be done earlier. Towards the end, when Tanya’s reading the part about Nicole saying a prayer - it’s like a rhyme, but it’s a prayer. Man, if this doesn’t eat you up … My wife and I — we were in tears.”

Shipp described Nicole as a doting mother of two and a loyal friend who loved making people laugh. 

“Nicole was a very fun person and she would say some of the funniest things,” he said. “I love telling this story: I first saw O.J. Simpson at the USC football game, but I never talked to him about it. One time, he and I were sitting there by ourselves and I said, ‘O.J., can we watch your 64-yard touchdown? I just want to see it sitting with you.’ And he went, ‘Ron, that’s the past. No man, we’re not going to watch that.’”

“Now I felt like a jerk,” Shipp continued. “I was like, ‘Gee, why did I bring that up?’ Because I never had before. He walked away and Nicole appeared. She goes, ‘I heard him. He watches himself all the time.’ And I started laughing. I just thought it was hilarious. She didn’t want me to feel bad.”

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Nicole Brown and O.J. Simpson (Photo by Gary Leonard/Corbis via Getty Images)

But Simpson’s marriage behind closed doors was far from a happy one. O.J. reportedly abused his wife regularly. In 1989, he pleaded no contest to a charge of spousal battery. In her diary, Nicole wrote how O.J. allegedly abused her on 60 different occasions and the abuse ranged from destroying her car to throwing her up against a wall. 

The diaries were reportedly found in Nicole’s safe deposit box in addition to photos of her beaten and bruised body, along with letters allegedly written by O.J. apologizing for his attacks.

In 1992, Simpson left O.J. and filed for divorce. The last time Shipp spoke to Simpson was May 19, 1994 — her 35th birthday. 

On June 12, 1994, Simpson and her friend Ron Goldman, 25, were found stabbed to death at her condominium in one of Los Angeles’ most exclusive neighborhoods.

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Shipp said he didn’t think twice to testify against the Hall of Fame hero nicknamed “The Juice” by fans.

Nicole Brown Simpson is seen bruised and battered in this photograph that was shown to the jurors in the O.J. Simpson trial. Nicole's sister Denise Brown testified that she took these pictures to document injuries at the hands of O.J. Simpson. (Reuters)

“When I saw those [crime scene] pictures, I made my decision right then and there I was going to testify,” he explained. “I felt that it was the only way I could have peace with myself, that I could go on living without nightmare after nightmare. Because at times I did feel like I failed her by not telling her, ‘Nicole, never go back.’ And I never said, ‘Never go back.’ Sometimes I wish I had said that. So by me testifying, sitting there, I felt it was well worth it.”

Shipp endured intense cross-examination. The defense attempted to portray him as a lying sycophant with an alcohol problem. 

During the trial, Simpson’s entries were not admitted into evidence because they were considered hearsay by the judge. However, O.J. was reportedly questioned about them during deposition leading up to the trial, in which he denied what was in the entires, according to Bustle.

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Despite his efforts in sharing his accounts, Shipp said there’s no denying the system failed Simpson as a domestic violence victim.

In this June 15, 1995, file photo, murder defendant, O.J. Simpson grimaces as he tries on one of the leather gloves prosecutors say he wore the night his ex-wife Nicole Brown Simpson and Ron Goldman were murdered, during the Simpson double-murder trial in Los Angeles. (The Associated Press)

“I’ll put it this way - O.J. was loved,” he said. “I’m telling you right now, I never found one bad thing with O.J. I had a blast with him and everybody loved him. If you look at the [Bronco] chase, all the people all over the freeway were cheering - everyone just loved this guy. I think the jurors had a hard time trying to find him guilty.”

“I remember looking at the jurors when I was sitting there, and usually when I would testify, I’d always tried to look at the jurors just a little bit and see if they bought what I was saying. Even though I was telling the truth, these people looked like, ‘Get this guy out of here,’ like they hated my guts. I just thought to myself, ‘Wow, this is going to be a rough one.’”

In 1995, O.J. was acquitted of the double homicide charges. The murder case is officially listed as unsolved.

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In 1997, after the victims’ families filed a wrongful death lawsuit against Simpson, a civil court awards a $33.5 million restitution to both families. Simpson later served nine years in prison for robbery and kidnapping over an attempt to steal back some of his sports memorabilia from a Las Vegas hotel room. He was released in 2017. The now 73-year-old has always maintained his innocence in the killings. 

Ron Goldman and Nicole Brown Simpson were murdered on June 12, 1994. (Reuters)

Shipp said he hopes the documentary will shed light on who his friend really was, as well as what she had to endure in her brief lifetime.

“I do miss her,” he said. “I really do.”

“OJ and Nicole: An American Tragedy” premieres Monday, Oct. 5 at 10 p.m. ET on ID. Fox News’ Jessica Napoli and The Associated Press contributed to this report.