RIP, one of the great free market economists.
A couple of notable excerpts:
Steve Horwitz eulogizes Buchanan at Bleeding Heart Libertarians, where he notes:
Understanding public choice theory is indispensable for understanding why good intentions are not enough to make the case for government intervention. If we want to understand why decades of government solutions have not been very successful at improving the condition of the least well off, public choice theory and Buchanan’s work is the place to start.
Whatever the result of arguments over his specific libertarian bonafides, he and his old partner Gordon Tullock, with whom he did the early foundational work in the school of economics that has come to be known as Public Choice, have unquestionably given libertarians a valuable intellectual and ideological tool. Buchanan and Tullock helped build a professional consensus and a rigorous scholarly apparatus around the notion that—despite what many economic professionals used to assume—the behavior of government agents can fruitfully be modeled the same way we model individual behavior in markets; that is, as largely motivated by maximizing the personal utility of the government worker or politician, not some empyrean concept of the “public good” or an overall “social welfare function” that a technical economist could calculate.[RIGHT]-- Brian Doherty