It was in my second or third programming side job when I was asked by the ramshackle finance marketing upstarts I was working for if it was possible to implement the almighty Income Tax Table (in Access, obviously). I had heard scary things about that beast. A few minutes of googling (I think was already Google?) and I realized that the law in question defined a simple linear factor that increases at certain thresholds, with a tax-exmpt base per threshold to correct for any jumps. I was so disappointed! Not so much by a scary mad beast that turned out to be all tame and reasonable but by the professions of finance marketers and tax consultants who routinely acted as if it was some arbitrary monstrosity that could only be dealt with in a lookup table.
in this era of handheld supercomputers, we're well beyond having to manually multiply out the formulas anyway. and tax forms are already basically one long formula where you just plug in the variable values in a step-by-step manner (and usually have a computer do the math for you).
but even so, a zero- (e.g., a single tax rate) or quasi-first-order (like a limited number of tax brackets) model makes no sense, when we can much better fit the desired effect with a slightly higher-order function for only a small complexity trade-off. better fit means reducing the exploitation surface.
tangentially, this is a relevant application of basic linear algebra and calculus to civics, which could be used as concrete motivation in the high school education of those subjects.
PS: if I were to design a state I would make it a part of the constitution that laws must either be written with placeholder variables for any concrete numbers you'd want to put into them or specify only concrete values for those placeholders and nothing else. And no single vote can contain both kinds at once.