The Los Angeles Police Department is currently testing a knife that was allegedly discovered years ago at the former home of O.J. Simpson, who was acquitted in the 1994 murders of Nicole Brown Simpson and Ron Goldman.

Capt. Andrew Neiman of the LAPD said in a press conference Friday that the knife had been in the possession of a now-retired police officer.

The story of the knife's origin is third-hand at best: Neiman says that the retired officer said that he had received it from a civilian who identified himself as a construction worker, and that the civilian said he found the weapon at the Brentwood property formerly owned by O.J. Simpson.

The dates of the alleged discovery and the transfer of the knife are not known. The house on that property has been torn down and rebuilt since the trial.

The Los Angeles Times notes that when Simpson was found not guilty in 1995, the absence of a murder weapon fueled searches and speculation:

"Finding the knife that killed the two had been an obsession of police and others in the wake of the murders."Authorities searched for the murder weapon for months after the slayings, and there have been many leads that went cold."A 15-inch knife with a retractable blade that Simpson purchased at Ross Cutlery in downtown Los Angeles briefly tantalized prosecutors in his criminal trial. ... Forensic tests later revealed that the knife was in pristine condition, with no scratches or bloodstains to suggest it had been used in the vicious June 12, 1994, double homicide."

The news that a knife may have been discovered at Simpson's former property — which was first reported by TMZ — has, accordingly, fascinated the public.

But Neiman repeatedly cautioned that the LAPD has not independently confirmed the retired police officer's story about the knife's origins, noting that the knife could be a "facsimile" or that the account of the knife's discovery could be inaccurate.

In the meantime, police are trying to vet the knife's backstory, and will examine it for bodily fluids and hair samples.

On the question of whether — if the story of the knife proves true — DNA could be recovered from a knife two decades after the fact, Neiman said: "We're hopeful — if this is involved, our investigators will submit it to the labs that are very good at what they do, and we'll see."

Neiman noted that because Simpson was acquitted and no other killer found, the Nicole Brown Simpson murder is currently an open case — and therefore, any evidence would be examined as part of an open investigation.

Because of double jeopardy, Neiman said, O.J. Simpson could not be charged with the murders again.

He also said he was surprised that a former LAPD officer would withhold evidence from investigators, even if the officer erroneously believed the Simpson case was closed.

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