Analysis: Chernoff Gets Tough on Prosecution Witness Elissa Fleak

Los Angeles - In aggressive cross-examination, Conrad Murray's lawyer Ed Chernoff questioned coroner's investigator Elissa Fleak's recollection of events, suggesting she had made a "substantial number of mistakes" in her investigation of the scene.

He highlighted that she had destroyed her original notes, left a thumb print on a syringe, and showed the court photos with latex gloves on a chair in the singer's bedroom, when her report said they were on the floor.

Fleak admitted that she has never conducted a "perfect" investigation, but insisted it was common practice to destroy original notes once the detail had been recorded in a formal report.

In a blow to the defense, she said she had requested Jackson's medical records, but that when she received them there were no records past April 2009. The singer died in June of that year.

FOX 11's Hal Eisner and legal analyst Robin Sax take a closer took at the tough cross-examination and who it ended up helping.