With the news of the discovery of a knife on the former property of O.J. Simpson, many are again speculating on the guilt or innocence of Simpson in the double murders of his former wife, Nicole Brown Simpson and her friend, Ron Goldman.

The knife, which Los Angeles police say will be tested to see if it is connected to the murders, was apparently kept by a police officer as a souvenir for nearly two decades.

Los Angeles police confirmed that the knife was recovered from the site of Simpson’s former Brentwood, Calif., mansion. The mansion was demolished in 1998.

If it turns out to be connected to the murders -- the cases are still active -- it will be perhaps the final piece of evidence in the case that led to "the trial of the century."

Nicole Brown Simpson and Ron Goldman were murdered on  June 12, 1994. OJ Simpson was found not guilty of the crimes on Oct. 3, 1995.

Here are five other pieces of evidence introduced at trial:

1. Blood drops: Blood drops were found on a gate at the murder scene and near bloody shoe prints at the crime scene. The drops, according to law enforcement, contained OJ Simpson's genetic markers. When Simpson was interviewed by police, he was photographed with a cut on his finger.

2. Matching gloves: An extra large Aris leather glove was found at the murder scene near the bodies. Another glove that appeared to be its mate was found on Simpson's estate. The gloves were covered in blood. The blood, again according to law enforcement, had Simpson's genetic markers as well as markers of Nicole Brown Simpson's and Ron Goldman's blood.

3. Crime scene hairs and fibers: Hairs described as similar to OJ Simpson's hair,  were found in a knit cap at the crime scene. Strands of hair recovered from Ron Goldman's shirt were microscopically identical to Simpson's head hair, prosecutors said at trial.

4. Bloody shoe prints: Bloody shoe prints were found at the crime scene.  They matched a size 12 Bruno Magli shoe. The shoe is a unique Italian-made model. Simpson said he didn't own a pair, but a photo of him wearing Bruno Magli shoes was later discovered  and entered into evidence. Simpson wears size 12 shoes.

5. Bloody socks: A pair of socks that had blood on them were found in Simpson's bedroom. The blood had Simpson's genetic markers and Nicole Brown Simpson's genetic markers.

Sources: The Los Angeles Times; The Associated Press