If you want to be a taxicab driver in King County, Washington (county seat, Seattle), be advised that you cannot wear shorts, sandals, jogging or warm-up suits or sweatshirts or similar attire, or “any similar clothing.” Fortunately, raingear is allowed (unless it looks like a warm-up or a sweatshirt?). Unfortunately, you may not wear underwear “as an outer garment.” King County Code Section 6.64.680
If you still want to drive a taxicab in Seattle, heed the following: You must wear “suitable clothes,” defined as “full-length pants, collared shirts and shoes.” (The Juice is out, since he only wears a collared shirt in Court, or for his website photo.) You must also be “well groomed,” which requires “bathing or showering on a normal basis” (Is there a King County “Bathing and Showering Inspector?”). You must have “hair that is neatly trimmed, beards and mustaches [that] are groomed and neatly trimmed at all times in order not to present a ragged appearance, and scalp and facial hair [that] are combed and brushed.” Oh, and a poorly groomed taxicab driver involved in an automobile accident will be presumed to be at fault. (Okay, there is no such presumption. But you had no trouble believing it, right?)
Now, if you are STILL interested, make sure you have no convictions for the following crimes or you’re out of luck, no matter how well you dress: use of a machine gun in a felony, murder, manslaughter, kidnapping, arson, robbery, and, of course, leading organized crime. King County Code Section 6.64.600. If you are really, really bored, the entire King County, Washington code may be viewed here.