Credit: Reellady / Foter.com / CC BY-NC-NDCredit: Reellady / Foter.com / CC BY-NC-NDOne of main subplots of the new-ish movie Mud, starring Matthew McCaughey, involves a poor Mississippi River Delta teen, Ellis, who helps his father catch catfish and sell clear plastic bags of the cleaned fish out of the back of the family’s beaten pickup truck. That food startup was all the income Ellis’s family appeared to have. Baylen Linnekin explains why the fictional family’s local enterprise would be unwelcome in the real-world state of Mississippi. Thanks to the state’s Catfish Marketing Law, every grocer and restaurant in the state must "provide the consumer with the country of origin and method of production of catfish,” a red-tape requirement that severely burdens small-scare entrepreneurs and limits out-of-state competition. If this sounds suspiciously like a protectionist law, Linnekin writes, that’s because it is.