Matt Yglesias doesn't think barbers need to be licensed:
Regulation of this sort seems totally unnecessary. People don’t die of bad haircuts, and since hairstyle is a quintessential matter of taste there’s absolutely no reason to think consumers can’t figure out for themselves who has a decent reputation as a cutter of hair. You can cut your own hair perfectly safely in your own house, and if you screw it up all that happens is you need to find a real professional to fix it. But what’s more, even if regulation were somehow a good idea, the composition of the board couldn’t possibly serve a legitimate consumer protection function. It’s overwhelmingly composed of people from the industry whose incentive is to limit competition and raise prices.
You'll be unsurprised to know that I don't have a lot to add on this subject. But I did get into a conversation about this with my haircutter once, and she pointed out that there's more to this business than you might think. It's true that clipping hair — which is the only side of the business that Matt and I ever see — isn't especially dangerous. But for more complicated jobs, hair professionals handle a lot of dangerous chemicals and they need to know how to use these properly to insure that they don't do some serious damage to their customers. That, apparently, is part of what they teach you at cosmetology school.
That's what she said, anyway. Alternatively, maybe it's all just a big scam. After all, plenty of women give themselves home perms and seem to survive the experience. Hair professionals should feel free to school us in comments.
UPDATE: Alex Massie adds some genuine data to this burning controversy: hairdressers in Britain, it turns out, don't require any kind of licensing at all. "Somehow," he says, "the country has survived an unregulated hairdressing and barber-shop industry all these years and may yet, with god's providence, do so in the future."
Well fine. Be that way. But just remember the story of the telephone sanitizers.