 In order to be licensed, drivers must have a valid license, pass written and location tests, a background check from the Honolulu Police Department, a physical exam and a clean driving record.A white placard is then placed on the front passenger side with a photo and information, while a sticker identifying the number is placed at the rear bumper sticker.In 2012, more than 1,632 vehicles in Honolulu were registered to operate as taxicab providers.