At a hearing yesterday, prosecutors made clear they are furious with Simpson's defence attorneys for failing to tell them about a clutch of witnesses unearthed by their investigators in an effort to exonerate the former American footballer of murder charges.
Although some witnesses were interviewed months ago, prosecutors said they only found out about the existence of most of them during the opening statement by Johnnie Cochran, Simpson's lead attorney. Failing to disclose witnesses or their statements to the other side is illegal - a point repeatedly made to Judge Lance Ito.
Christopher Darden, prosecuting, told the hearing at Los Angeles Superior Court - which was in the absence of the jury - that the "dream team of America's finest lawyers" had "intentionally and wilfully disregarded the basic and fundamental rules of discovery" and impinged on the prosecution's right to a fair trial. "How are you going to unring the bell? How are you going to bring back the bullet once it's already fired?" he asked.
He demanded the jury be instructed to disregard much of the witnesses' evidence, and asked for permission to reopen the prosecution's opening statement - a highly unusual move. He also asked for a brief delay in the trial to allow the Los Angeles District Attorney's office to investigate the witnesses' backgrounds.
The witnesses range from a spousal abuse expert and the maid of O J Simpson, who was allegedly struck by Nicole Brown Simpson, to a doctor who will testify that Simpson should have been - but wasn't - drenched in blood, had he committed the murders. Simpson is accused of stabbing to death his ex-wife and Ronald Goldman outside her house in Los Angeles last June.
Mr Darden singled out one of the surprise witnesses for particular attack: Mary Ann Gerchas, whom the defence say saw four people running from the murder scene at 10.45pm on the night of the killings. He said that she owed $10,000 (£6,000) in bad cheques, had defrauded a hotel chain of $25,000, and may not even be the person she claims to be: "We are concerned that she is not the real Mary Ann Gerchas".
If true, this could be a considerable setback for Simpson's defence as it would be a blow to their credibility to the jury if the judge tells the jury to discount some of the witnesses which they revealed with such flourish earlier this week.
The matter was heard after the judge put proceedings on hold for several hours to allow prosecutors to prepare a motion demanding sanctions against Simpson's lawyers.
On learning of the witnesses, prosecutors immediately ran their names through police computers.
The Deputy District Attorney Christopher Darden told the judge that they included "heroin addicts, thieves ... and one court-certified pathological liar."