Each state has adopted a variety of rules regarding what facts are deemed proper evidence. Only what a court deems admissible evidence may be considered in reaching a verdict of guilt or innocence. Evidence that is suppressed because it was gathered in violation of the Constitution may have a profound impact on the guilt of a defendant. However, the ability to limit what information a juror has access to is becoming increasingly more difficult to control.
The prevalence of smartphones and tablets allows jurors to gather data about a defendant, victim, crime scene, or witness that was not authorized or even presented at trial or in fact was specifically prohibited by law to be used to determine guilt. But, the temptation to know "the truth" can drive jurors to ignore the mandates of the Constitution and the laws governing proper evidence.