Federal prosecutors in the United States get to pick their spots. The vast majority of criminal conduct (think theft, burglary, assault, sex crimes) is prosecuted on the state and local level, and most federal crimes, from drug possession and distribution to various forms of fraud, are also violations of analogous state laws. So unless a uniquely federal crime is involved (such as immigration, terrorism, espionage, or crimes against federal officers or property), the feds almost never have to take a case, lest it go unpunished.
This is why being a federal prosecutor is such a great job, but also why getting prosecuted by the feds usually takes some doing. Sure, that check-kiting scheme, marijuana distribution conspiracy, or even insurance fraud grift you have going are all technically prosecutable by Team America, but federal law enforcement generally feels it has more important things to do. Unless your scheme involves either very big money, large amounts of illegal drugs, or there is another good reason to pique the feds’ interest, your local prosecutor is your biggest worry.
This is why Bernie Madoff faced federal prosecution for various flavors of fraud owing to the massive dollar amounts he bilked his clients out of, but if you call your local federales and present rock-solid evidence that you were taken for a few grand by a rogue contractor who falsified his invoices and sent them to you via the U.S. mail (mail fraud) after calling you (wire fraud) to falsely assure you that your new deck was made of pressure-treated lumber when it wasn’t, a federal prosecutor would likely never take the case.
So why is it that Lori Loughlin (Aunt Becky!), Felicity Huffman, a managing partner of a major New York law firm, and a veritable conga line of comically privileged helicopter parents from Los Angeles, New York, and elsewhere descended on the Moakley Federal Courthouse in Boston to plead guilty to federal charges for illegally scheming their children into college? Moreover, how is it that almost all of these parents have been or will be serving at least a few weeks or months in federal prison for a scheme that seems at times as much comic as tragic? From afar, “rich family buys kids’ way into college” seems like the ultimate “dog bites man” headline.