Distributing private images online without a person's consent will be a felony under a law signed by Illinois' Governor Pat Quinn.
The measure takes effect Thursday and addresses so-called "revenge porn" in which a former romantic partner posts private pictures or videos in retaliation.
Democratic state Sen. Michael Hastings is a bill sponsor. He says it is "psychological abuse to the highest degree."
His office says it's already illegal to put identifying or graphic information without consent on pornographic websites. But state law didn't previously address privately-shared images.
Quinn said Monday that cyberbullying can have lasting and devastating effects. He says the law cracks down on perpetrators and will prevent more people from becoming victims, most of whom are women.
Critics had expressed free speech concerns.