Not sure if this applies to the ancestor comment, but in New York City, the lights are on indicating when they are full, available for hailing or off duty. It

Not sure if this applies to the ancestor comment, but in New York City, the lights are on indicating when they are full, available for hailing or off duty. It is also illegal to not pick up a fare there, but drivers have refused in the past (depends on what you look like, where you are, the time of day, if you have airplane luggage, etc.)