The only exception to this occurs when a group of workers is receiving a wage actually below its market worth. This is likely to happen only in rare and special circumstances or localities where competitive forces do not operate freely or adequately; but nearly all these special cases could be remedied just as effectively, more flexibly and with far less potential harm, by unionization.
It may be thought that if the law forces the payment of a higher wage in a given industry, that industry can then charge higher prices for its product, so that the burden of paying the higher wage is merely shifted to consumers. Such shifts, however, are not easily made, nor are the consequences of artificial wage-raising so easily escaped. A higher price for the product may not be possible: it may merely drive consumers to the equivalent imported products or to some substitute. Or, if consumers continue to buy the product of the industry in which wages have been raised, the higher price will cause them to buy less of it. While some workers in the industry may be benefited from the higher wage, therefore, others will be thrown out of employment altogether. On the other hand, if the price of the product is not raised, marginal producers in the industry will be driven out of business; so that reduced production and consequent unemployment will merely be brought about in another way.
When such consequences are pointed out, there are those who reply: “Very well; if it is true that the X industry cannot exist except by paying starvation wages, then it will be just as well if the minimum wage puts it out of existence altogether.” But this brave pronouncement overlooks the realities. It overlooks, first of all, that consumers will suffer the loss of that product. It forgets, in the second place, that it is merely condemning the people who worked in that industry to unemployment. And it ignores, finally, that bad as were the wages paid in the X industry, they were the best among all the alternatives that seemed open to the workers in that industry; otherwise the workers would have gone into another. If, therefore, the X industry is driven out of existence by a minimum wage law, then the workers previously employed in that industry will be forced to turn to alternative courses that seemed less attractive to them in the first place. Their competition for jobs will drive down the pay offered even in these alternative occupations. There is no escape from the conclusion that the minimum wage will increase unemployment."
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"As to the prices, wages and profits that should determine the distribution of that product, the best prices are not the highest prices, but the prices that encourage the largest volume of production and the largest volume of sales. The best wage rates for labor are not the highest wage rates, but the wage rates that permit full production, full employment and the largest sustained payrolls. The best profits, from the standpoint not only of industry but of labor, are not the lowest profits, but the profits that encourage most people to become employers or to provide more employment than before."
Henry Hazlitt “Economics in One Lesson.”
To those who are downvoting: There are no illegal people, there is no illegal two-party consensual trade.