I would believe excessive smoke could lead to PC to check your tank if it's known that off road diesel causes the condition. But a broken tail light? I don't think so. That's just enough for a stop.
Locking fuel cap means nothing. If an officer has true probable cause he can break off a fuel cap if need be to discover further evidence of anything illegal. Diesel fuel is no different than 10 kilos of cocaine in your spare tire. If it's in the there then he has to have some real probable cause to look in the tire such as a dope dog alerting on the tire. An officer stopping you for a minor traffic infraction and dipping in your tank with nothing else to go on other than the small traffic infraction is an illegal seach.
Locking fuel cap means nothing. If an officer has true probable cause he can break off a fuel cap if need be to discover further evidence of anything illegal. Diesel fuel is no different than 10 kilos of cocaine in your spare tire. If it's in the there then he has to have some real probable cause to look in the tire such as a dope dog alerting on the tire. An officer stopping you for a minor traffic infraction and dipping in your tank with nothing else to go on other than the small traffic infraction is an illegal seach.
The way I understand it is the officer has to ask to search a vehicle in Pa during a routine traffic stop. If the item is locked (trunk, glovebox, etc) or if you refuse when asked, they need a warrant stating probable cause.
Also I don't know anyone that has been caught running red fuel, although I hear the fine here is $10K per gallon used. Since they have no way of determining how much is used, they supposedly get you for the capacity of the tank. Don't know if that is in fact true, but its not worth the risk to me.
I researched the laws here in nevada.
It would run you about $3k if you get caught with it in your tank. its like # of gallons x tax x 10% and a 2,500 max admin fee. and suspend license for not more than 30 days
second offense in 4 years is a $5k max admin. fee and suspend license for not more than 60 days
third offense or more in 4 years is a $10k max admin fee. and revoke license
The suspended license will be dertimed case by case depending on the amount of admin fee charged...
Also, metro does not carry equipment to test for dyed fuel.
Highway patrol can check for died fuel and carries equipment.
They test over a hundred vehicles a month...and rarely have a citation issued.
They are not allowed to stop you and check for dyed fuel unless you are seen using it, or you are stopped for another violation. Also, you can be checked at weigh stations and safety check points.
Procedure for checking is:
drawing fuel with a tube for a visual check, if it appears to be dyed, they take the sample and send it to the lab to determine if it has dye in it. (a min. ppm of dye that I dont know.)