Or if you walk down the street dressed like this.
According to everything I’ve heard, and my Criminal Justice major “I wanna be a cop” buddy, (in America) you do have to identify yourself to a cop when asked. They can’t demand your “papers” if you’re not doing a licensed activity like driving, but they do have the power of detainment (I demand you tell me if you witnessed something back there, I want to see if you’re as drunk as I think you are, you remind me of this bail-skipper I arrested last month).
As for driving, I’ve even gotten out of the ticket of not having my license on me by being able to recite my DL number, which matches the name on the registration for the car.