 The popularity of forensic crime television shows supposedly gives rise to many misconceptions about the nature of forensic science and investigation procedures among jury members . The CSI effect is hypothesized to affect verdicts in two main ways : first , that jurors expect more forensic evidence than is available or necessary , resulting in a higher rate of acquittal when such evidence is absent ; and second , that jurors have greater confidence in forensic and particularly DNA evidence than is warranted , resulting in a higher rate of conviction when such evidence is present . While these and other effects may be caused by crime shows , the most commonly reported effect is that jurors are wrongly acquitting defendants despite overwhelming evidence of guilt . In particular , prosecutors have reported feeling pressured to provide DNA evidence even when eyewitness testimony is available . In one highly publicized incident , Los Angeles County , California District Attorney Steve Cooley blamed actor Robert Blake 's acquittal on murder charges on the CSI effect . Cooley noted that the not guilty verdict came despite two witness accounts of Blake 's guilt , and claimed that the jury members were " incredibly stupid " . 
