Duran Duran's tour bosses had to write down the age of consent wherever they travelled to ensure the group didn't get arrested.
The 'Ordinary World' rockers - made up of singer Simon Le Bon, bassist John Taylor, drummer Roger Taylor and keyboardist Nick Rhodes - were propositioned by so many women in the US that it was essential they were aware of the legal age that sex was permitted, but John admits it was "months" before he was told what the numbers on his itinerary meant.
In extracts of his forthcoming memoir, 'In the Pleasure Groove', obtained by the New York Post, he explained: "Of absolute necessity for any touring musician is the itinerary.
"In the left-hand corner of each page of the US itinerary, there was a number, usually 18, 21, or 20.
"It was months before I was let in on the secret. The numbers referred to the legal age for sexual intercourse in that particular state."
John admits he turned to drugs the tour because he was lonely, and during one recording session at the Power Station recording studios in New York he had "unlimited" access to cocaine and had "never seen more drugs" in his life.
He added: "Everyone wanted to party with me, but behind the party face, I was caught up in a vortex of fear, arrogance, loneliness and extraordinary popularity."