US prosecutors hit out Friday at the \"ever-changing defense\" by lawyers for the doctor of late pop star Michael Jackson, rejecting charges that they were keeping the medic\'s team in the dark. The legal tussle came during a technical hearing called by Judge Michael Pastor in the absence of the jury to discuss the upcoming list of defense witnesses in the trial of doctor Conrad Murray. The 58-year-old doctor is accused of involuntary manslaughter over Jackson\'s death, which was primarily due to \"acute propofol intoxication,\" combined with the sedatives lorazepam and midazolam, according to coroners. Murray\'s team said they planned on calling about 15 witnesses when the case comes back to court on Monday. Attorney Nareg Gourjian said they would call \"police officers, experts, character witnesses,\" and provide a list before calling them. Prosecutor David Walgren asked how many medical experts would be called to testify and was told two, maybe three. The prosecution is also leaning on the testimony of anesthesiologist Steven Shafer, an expert in propofol, who took the stand on Thursday and will continue on Monday. Murray\'s decision to give propofol on top of two other sedatives, along with other failings, produced a \"perfect storm\" that led to the King of Pop\'s death on June 25, 2009, critical care specialist Nader Kamangar told the court on Thursday. But the defense said Shafer will present new \"scenarios\" to the court of which they have not been informed in advance. \"We are in the dark regarding where this is going,\" said defense attorney Michael Flanagan. Walgren hit back that there was \"nothing new, nothing surprising. I find it hard to believe that they are in the dark.\" He added that Shafer was likely to be the prosecution\'s final witness. Judge Pastor said he hoped that all the witness testimonies could be wrapped up by the end of the next week. But he also expressed concern about the exhibits that would be presented to the jury. \"There are a significant number of exhibits that contain material that may be harmful,\" he said, referring to bottles of the powerful anesthetic propofol and other medications. \"Certain exhibits won\'t be sent to the jury, but they can ask for them. They will be viewed only by request.\" Murray\'s defense lawyers have claimed that Jackson was a desperate addict who could have given himself an extra dose of propofol while the doctor was out of the room. In a surprise move, the defense has dropped its claim that Jackson could have drunk the propofol, while leaving open the possibility he could have injected it via an intravenous tube inserted into his leg.