Surrounded by his famous collection of time pieces, Judge Lance Ito is clearly impatient with the pace of the Simpson trial. In a serious setback for the defense today, Ito ruled that he will not allow the testimony of disgruntled FBI agent Frederic Whitehurst. The decision also means that FBI toxicologist and former prosecution witness Roger Martz will not have to return to the stand. James Willwerth reports from the trial: "Ito ruled that it was not relevant for jurors to hear Whitehurst saying he believed that Martz had altered lab results in another case, testimony the defense hoped to use to taint Martz' work on the Simpson case. Essentially, this ruling means that the defendant does not have an absolute right to throw something up against the wall and see if it sticks, which is what Johnnie Cochran has been doing throughout this trial. At some point the judge has to say that some testimony really isn't relevant to the case. Ito feels the jury has waited long enough. He wants to wrap up testimony as quickly as possible." Ito said late Tuesday that testimony would end by Friday, and closing arguments would begin next Tuesday -- nearly a year after jury selection in the trial began.