zman wrote:plenty of poor people went to Yale and columbia in the 50s. I don't think the quality of education is that much better at yale/Columbia or a state school. It's about even.
In my opinion, you are focusing too heavily on the "educational quality" aspect of a given school. Higher ed institutions, ESPECIALLY law schools, tend to be more valuable as signaling devices rather than as actual measures of practice-ready graduates. You don't hire a Yale Law graduate because the faculty at Yale is so much more adept at teaching law than any other school (matter of fact, some people argue that they're less adept at teaching practical skills). You hire them because you can be sure you're hiring someone who is smart and capable. In most fields the admissions process has already "sorted" students, so employers can hazard a guess as to how smart/capable you are without needing to interview every resume that lands on their desks.
The same principle holds true today for a college education, despite the fact that most students are graduating with little to no practical skills (which they will presumably learn at their positions). Having a college degree demonstrates that you are a) Smart enough to have gotten into College X, however smart that may require, and b) A decent enough worker so as to have graduated, or to have received a GPA of x.xx. Note that none of the above suggests at any point that you have learned anything.
Also, I would dispute the notion that "plenty" of poor people went to Yale and Columbia in the '50s. By 1960 the tuition at these schools is around $1500, which is about half the median income of the time. So in the absence of loans, you're talking about perhaps two years' salary for a middle-class family, not including room/board/books/whatnot (and of course, most households are one-income at this point). That is perhaps doable, and it contributes to the increasing presence of the middle-class at elite educational institutions during the post-war years (along with standardized testing and the GI Bill). But if you were poorer, and school costs maybe three or four years' salary? No way, not without loans or a scholarship.
Also, this analysis necessarily excludes women and minorities, meaning that even in the whitest time in American history (late 50s/early 60s), 55% of the population is shut out by default.