How do we know that these fine upstanding gentlemen weren't simply acting as innocent couriers of charity collected over a year at local hispanic churches to help the oppressed in Latin Americ?
This presumption of guilt is even worse than "Minority Report". How far can a person get from the southern border and still be in the lower 48 than Maine? How does that argument work in court? Yeah, even though they were thousands of miles away from the border, and despite any evidence or confession we know beyond a shadow of a doubt they were going to cross the border.
Even if it was drug money (most likely), how do they know it was going to leave the country and not be used to buy land or anything else legally purchasable? In that case, the "smuggling" charge is bogus - doesn't one actually have to commit the crime or admit to conspiring to commit a crime to actually have the charge stick? Or has our legal system so degenerated that the hypothetical is no different than the actual.
Clearly Maine wanted the loot and knowing after interrogation that the couriers wouldn't challenge the seizure in court saw this as an opportunity to steal over a million dollars. In a just world, they would have reported the truck to the border patrol and asked them to keep an eye out - but doing that would have forfeited enjoying the full plunder. Justice be damned, its all about the money.