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Actually, it can. In particular 3 years in the early 20’s. What we might refer to generally as “judgment” or “maturity” is an intellectual function which is largely a function of the operation of the prefrontal cortex - which is the last part of the brain to develop, and typically is still physiologically unmatured into the mid-20’s. This is not a phenomenon which is novel; recent research simply confirms long time observations. Why do you suppose the Constitution requires a Congressman to be 25, a Senator 30, President 35?</p>
<p>Younger people excel at learning facts and concepts - that’s a brain function which declines with age. But “the so-called “executive” functionsplanning, setting priorities, organizing thoughts, suppressing impulses and weighing the consequences of one’s actions” are things which are generally not fully developed until one is - well, roughly the minimum age at which most people complete law school.</p>
<p>As for how it’s done in other countries, I suspect that in most developed nations an individual is not certified to perform all of the functions a licensed US attorney is licensed to perform at an earlier age than is true here. The mechanism may be apprenticeship, tiered qualifications, etc. - but I suspect that full qualification along the lines of bar admission here does not occur until the mid-20’s elsewhere as well.</p>