This is a really great talk from about a month ago. He has some interesting criticisms of Hayek here. I'm not qualified to say if he's characterizing Hayek well because I haven't read much of Hayek on the law. Even if its a caricature, it's probably the sort of position many people hold so his criticism I think is still valuable and interesting. Lots of really good thoughts here about the difference between efficiency at the micro level and efficiency at the macro level, as well as understanding rules as externalities or public goods.
Watching this inspires something of an autobiographical digression, if you care at all: James Buchanan had me quite excited about George Mason University when I read some of his stuff as an undergraduate at William and Mary. I especially appreciated his work on constitutional economics. I also wrote a few papers on economic geography, which is when I first came into contact with a guy named Paul Krugman, specifically his work on and the work of people at the Santa Fe Institute on "emergent order". The summer after my junior year I attended an experimental economics workshop at George Mason, where I became even more enthusiastic after meeting Vernon Smith and reading Hayek there, and hearing him talk about these same ideas of emergent order that I had first read about in Krugman's work. I had read some Hayek before, but that was the first time I had ever heard of the Austrian school as a school of thought. It was easier to get my master's at night at George Washington University, which was a couple blocks away from work for me. So any thoughts about Mason or anywhere else (I was also always excited about the University of Maryland) was shelved for a while. In the interim I learned how political the department was and I never ended up applying this last year. That was kind of surprising to me. At George Washington the political views of only one of my professors was clear. At William and Mary two were quite clear. All three of these cases were liberal Democrats, which wasn't particularly surprising. Over all though I had no clue. College faculty are bound to be liberal, but economics faculty specifically obviously weren't spouting leftism or anything like that. I just didn't know - politics simply never came up all that much, and I still don't know. Anyway, it's an odd thing. What I like about James Buchanan is that he's always so clearly concerned with understanding how the economy works. The political affiliations didn't really blare out from him for me. Always good to listen to or read - a brilliant mind.
UPDATE: And since I mention my early interest in Krugman - I never read his columns back then. I didn't even realize he had one until after I graduated. So I didn't really realize Krugman had strong political views until I had already read a lot of his stuff and until he became the guy that first explained emergent order to me. For a lot of you it's just the opposite, I imagine - the columns and blog posts of Krugmans are the first introduction you had to him (for many of you, perhaps the only thing you've ever read of his) and it was someone like Hayek that introduced you to emergent order.