Cook County Chief Judge Timothy Evans ordered the ban on the devices to prevent gang members from intimidating witnesses and even potential jurors in criminal cases.
"Judges brought their concerns to me that people attending court proceddings were using their cell phones to photograph witnesses, judges, jurors, and prospective jurors. They also said persons appeared to be texting testimony to witnesses waiting their turn to testify outside the courtroom, while others were attempting to stream live to media comments by judges from the bench," said Evans, according a news release.
"The court is sending a strong message to gang members and others that any attempts to intimidate witnesses, jurors, and judges in court will not be permitted," Evans also wrote in the release. "The ban will help to ensure that justice is properly done by preserving the integrity of testimony and maintaining court decorum."
The ban will affect only those courthouse facilities in which criminal matters are heard.
It takes effect January 14, 2013.
Anyone violating the ban could face prosecution for contempt of court.
Those visiting the courthouses on official business and with approved identification are exempt from the ban.