A number of people, including many commenters here and even alleged conservative James Joyner think you should need a professional license to become a barber because you might hurt someone with a straight razor. Uh huh. At best this would be an argument for regulating people who do shaves with a straight razor, which would be considerably narrower than current comprehensive regulation of hair stylists.
Meanwhile, though “torts and the free market will take care of it” isn’t the answer to everything, it’s surely the answer to some things. Getting some kind of training before you shave a dude with a straight razor is obviously desirable in terms of strict self-interest. If you screw it up in a serious way, you’ll face serious personal consequences and the only way to make money doing it—and we’re talking about a very modest sum of money—is to do it properly. People also ought to try to think twice about whether their views are being driven by pure status quo bias. Barbers are totally unregulated in the United Kingdom, is there some social crisis resulting from this? Barber regulations differ from state to state, are the stricter states experiencing some kind of important public health gains?
Last you really do need to look at how these things play out in practice. If you just assume optimal implementation of regulation, then regulation always looks good. But as I noted in the initial post the way this works in practice is the boards are dominated by incumbent practitioners looking to limit supply. One result is that in Michigan (and perhaps elsewhere) it’s hard for ex-convicts to get barber licenses which harms the public interest not only by raising the cost of haircuts, but by preventing people from making a legitimate living. States generally don’t grant reciprocity to other states’ licensing boards, which limits supply even though no rational person worries about state-to-state variance in barber licensing when they move to a New Place. In New Jersey, you need to take the straight razor shaving test to cut women’s hair because they’re thinking up arbitrary ways to incrementally raise the barrier to entry.
In principle, you could deal with all these problems piecemeal. But realistically this sort of problem is inevitably going to arise when you pit the concentrated interest of incumbent haircutters against the diffuse interest of consumers. It’s hard enough to make sure that really important regulatory functions related to environmental protection, public safety, and financial stability are done properly.