During periods of prosperity, such as the 20s and again in the 60s and 70s, there was rapid growth in the real GNP, which is a major determinant in the demand for legal services (Pashigian 1977), rather than what government regulations are momentarily fashionable. Evidence indicates that historically there have been fewer lawyers rather than more lawyers than needed. Supply adjustment is slower than demand shifts, and the rate of return to legal education rises when a demand increase is slowly followed by a supply response. Lawyers can transfer to other business fields easily, at the first hint of a higher return to any parallel profession.

Abel (1986) wrote that the supply of lawyers is growing because the legal profession lost control of entry. This is a prima-facie indicator that when the legal profession did control the entry, numbers were plausibly artificially limited by the controllers. .

Abel & Lewis (1988) wrote that the ABA lost control of the supply of lawyers, when schools, which had a goal of educational growth, took over control of the exact numbers of future lawyers enrolled. Graduation rates rose from 60% to 90%, under school-imposed entrance requirements.

Halliday (1986) said that the market can be lost through under-control. He believed that the ABA still controlled entry to the legal profession in 1986, while Abel (1986) argued otherwise.