What harm do minimum wages do?

I know research is hard, and these issues are fraught with complexities and challenges in acquiring data, but it still boggles my mind just how many macro economic theories don't have strong empirical data to support them.

> Textbooks state that, in the absence of a minimum wage, a worker is paid his “marginal product of labour”, which means the value of what he produces.

> Just as a monopolist can set prices higher than would be the case in a competitive market, a monopsonist can set prices artificially lower.

A lot of economic arguments forget these ideas. The labor market is not a free market: companies have more power in negotiation, they have more information and, most important of all, they can deal with a job opening not being covered most of the time. Workers can't usually live too much without finding a job.

That's why minimum wage laws and workers rights are important. Companies will always push for lower wages wherever they can, without a care for the actual wealth created by the worker. The only way to counter that push is by giving more power to the worker, and in low-skilled fields with lots of available workers, you need to do that through regulations and subsidies.

(can't read the article, but I've read and thought a lot about it)

I'm on the fence about the net cost/benefit of localized minimum wages. I think that a federal minimum wage (or at least, a high one), and to some extent, state minimum wages, are a bad idea. The Fight for $15 movement came from expensive cities, and it might be the right policy for those places. But it would severely distort and crush lower-cost cities and states. The right policy for San Francisco isn't necessarily right for Birmingham. It's one thing to have uniform national laws for human rights. But the nominal value of $15 means something very different in different parts of the country.

It seems to me that the right policy to increased pay for low wage jobs would be to set the minimum wage so a full time job at that rate puts you at some multiple of the metropolitan/micropolitan area poverty line. Wages would automatically increase with costs in a predictable way, and local economic conditions determine the rate. State or federal minimum wages could set a floor but acknowledge that regional differences matter in economics.

What if the strong empirical data were against the interests of the rich and powerful?

They couldn't afford to base policy on those then!

Right, many minimum wage opponents focus on the scenario where someone is worth e.g. $14/hr to a business, and rightly point out that this person won't be hired with a $15/hr min wage.

BUT without a minimum wage, someone worth $50/hr can be paid $5/hr if anyone can do the job. It strikes me that this situation is far more common than the first scenario, and minimum wage opponents tend to ignore it in their arguments.

Minimum wage sets a floor for the market. That could theoretically increase unemployment in some industries with razor thin margins, but it's far from a given.