Most states forbid anyone from recording a private phone conversation unless at least one of the people involved in the conversation knows it's being recorded. Many states require at least two people know about the recording; some require that everyone know.
That's why, when you call your insurance company, bank or other giant corporation's help desk, a recording tells you the call may be recorded "for quality control purposes."
The call will be recorded, but for purposes of giving the company evidence of what happens during the conversation. You don't have to stay on the line if it's being recorded, but the company is off the hook for eavesdropping in almost any state after letting you know you're being recorded.
The Illinois Eavesdropping Statute stretches the boundaries of what is appropriate to overhear by making it illegal for anyone to audio- or videotape an event or conversation without the knowledge and approval of everyone involved.
It would never be prosecuted, but the law would technically make it illegal to video-record a snippet of a football or basketball game – especially recording the cheering crowd rather than the players – without getting the permission of everyone in the crowd beforehand.
Neighbor's voice caught on videotape of your kids in the backyard? That's a felony
The Illinois Eavesdropping Statute doesn't kid around, either. Violating it is a Class 1 felony with penalties ranging up to 15 years in prison.
That's what Chicago artist and photographer Christopher Drew, 61, faced after being arrested in 2009 for selling patches on the street without a peddler's license.
When police approached, Drew, uncertain of their intentions, hit the Record button on a tape recorder in his poncho. It recorded the conversation between Drew and the arresting officer. When police found the recorder it got Drew a felony indictment for eavesdropping on a conversation in which he was a participant, the other party was a public official engaged in activity required to be treated as a public record.
“It was impossible for me to imagine a law based on privacy would make it illegal for me to tape a public conversation by a public officer on the public way who was arresting me,” Drew told the Chicago Sun-Times. “I should have the right to bring evidence into court of what that officer says to me in public.”