I don’t think this it’s worth being reported for asking for a source on this kind of claim. I would argue of a middle ground though. I think field tests origins came from a good intent of trying to distinguish intoxicated drivers but has morphed over the years and used to give reason to search your belongings. I think the original post is wrong, the intent is not to arrest people but they are commonly used as a means to get cause to search your vehicle.

And I don’t have a source, so it’s anecdotal but one of those things where you read enough of these cases and even see how cops are trained that the intent for most stops unrelated to genuine traffic violations is to get cause to search the vehicle.

I think back to some of those corridors within the United States where law enforcement abuse cash forfeiture laws to take peoples money.