There are a lot of laws about head and taillights, which a lot of people misunderstand.
The laws are federally mandated safety equipment. This means all 50 states follow the same rules. A vehicle needs to meet these rules just to be allowed to drive in this country. Automakers must design their cars to meet them.
For taillights, they must have reflectors that can be viewed fron the side and from the rear. They must reflect RED light. No other color is legal. The non-reflective lenses don't need to be red, but when the lights are on, the bulb/leds must produce clear clean unobstructive red light. The turn signals need to be amber or red in the rear and the reverse lights need to be white. Lisence plate bulbs must be white.
Up front, amber reflectors must be present at the side corners. This is why clear corners are illegal. Parking lamps/turn signals must be amber and no more than 4 forward facing white lights can be present. Light also must have a certain minimum spacing between them. That's why the '68 shelby's center fog lights were discontinued after 1 year. They were made illegal. All these guys converting to center fogs on their 05+ are technically running illegal setups.
Taillight or headlight blackouts are 100% illegal. They block the turn signals. A lot of guys say they are legal in the day but that's BS. They are illegal 24-7
If you get rear-ended with modified taillights (smoked, tinted, all-white, etc) you can be found partially responsible if someone catches it.