Still haunts her. Marcia Clark, the famed prosecutor behind O.J. Simpson's high-profile murder case from 1995, looked back at the verdict and its still-lingering aftermath in a new interview with Dateline NBC on Sunday, March 6.

The attorney, 62, gave a candid assessment at all of the emotions she felt after hearing the "not guilty" verdict from the jurors.

"I felt horrible. It was physically painful," Clark told Josh Mankiewicz during her sit-down chat. "You know, that was not justice. And I thought of Ron and Nicole and thought, 'This is wrong. It's so wrong.'"

In June 1994, Simpson's ex-wife Nicole Brown Simpson and her friend Ron Goldman were found stabbed to death outside of her home, and the leading suspect was Simpson. After a frenzied, highly-publicized eight-month trial, the NFL player was ultimately acquitted of their murders in 1995.

While the trial was more than two decades ago, Clark revealed to NBC that she still blames herself for that loss of justice. "I always do. I do. I mean, I was the one trying the case," she explained. "But at the end of the day, we really — there was no way to reach that jury. There was no way to make them believe. There really wasn't."

Following the verdict, Clark left the district attorney's office without knowing the next path in her career. "I was done," she said. "I was done. For a while there it was a loss of faith. I was exhausted. I was physically and emotionally drained." Clark eventually went on to write several books, including her best-known work, Without a Doubt, about Simpson's case. She is currently a special correspondent for Entertainment Tonight and a contributor to The Daily Beast.

The case is currently experiencing a resurgence of interest with the recent release of FX's new miniseries The People v. O.J. Simpson: American Crime Story, in which Clark is played (impressively!) by Sarah Paulson. This past Friday, March 4, a shocking, possible new development to the murder case was revealed and confirmed by the Los Angeles Police Department.

A buck knife that was found by a construction worker on O.J. Simpson's property was turned over to police and submitted to labs for formal testing. Though no link has been made yet, police reiterated to the public that the murders of Goldman and Brown Simpson is still being investigated.

"The bottom line is that with all cases that remain open ... unless there's an actual arrest or conviction to prove that we have actually closed the case, the cases remain open," the LAPD said during a press conference on Friday.

Clark, however, was incredibly skeptical — and somewhat hopeful. "I really don't know what to think of it," she told Entertainment Tonight on Friday. "I mean they recover DNA on mummies in Egypt," Clark explained. "It's entirely possible that if there is some DNA to be recovered that it could be found.”

Her Dateline interview was conducted before Friday's news about the knife.

Watch the video above.

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