|Original Airdate||November 13, 2003|
|Previous Episode: Jackpot|
|Next Episode: After the Show|
Invisible Evidence is the seventh episode of season 4 of CSI: Crime Scene Investigation
During a preliminary trial for the rape and murder of a 19-year-old woman, the crucial evidence, a bloodied knife, is discarded because it was secured from the defendant's car without a warrant. With only 24 hours left before court has to let him walk, the team pools their resources together in an attempt to find other evidence that can place the defendant behind bars.
Sheriff Rory Atwater is introduced for the first time.