Harvard's Class of 2022 is made up of over 36% legacy students, according to The Harvard Crimson. The year before, the share of the freshman class was just over 29%. (CNBC Make It has reached out to both The Crimson and Harvard's admissions office to confirm these figures.)
As of 2015, legacies were five times more likely to get into the world-famous university than applicants without relatives who went to Harvard.
Stanford University gives legacies a significant advantage as well. "It used to be that every application would be read twice. Now, only one reading is guaranteed, although — thanks, Mom and Dad — every legacy application still gets two sets of eyes," a 2013 Stanford Magazine article about the school's admissions process reported.
Across the top 30 schools in the U.S., one review from 2011 discussed in the Washington Post found that children of alumni "had a 45 percent greater chance of admission" than other applicants.
The issue of legacy admissions is especially pertinent in light of recent news: Federal prosecutors have brought charges against 50 people in a sweeping college cheating scandal in which wealthy parents allegedly paid a collective $25 million to help their children get into top colleges and universities, including Yale, Stanford and USC.
As prosecutors acknowledged, and as critics have pointed out, there are already several legal ways for wealthy parents to work the system. Legacy admissions, especially at elite institutions, for example, is one such way a lucky few gain a distinct advantage.
The concept has been controversial since its beginning. In the early 20th century, universities introduced a preference for legacies to exclude less desirable applicants, such as immigrants, and to keep their campuses homogeneous, Think Progress reports.
For instance, Princeton adopted a comprehensive admissions process in 1922 similar to the one Dartmouth created in 1919, which stated that "all properly qualified sons of Dartmouth alumni and Dartmouth college officers" would be admitted. After the new policy led to a drop in Princeton's Jewish student population, the chairman of Princeton's Board of Admissions acknowledged that he had wanted to solve the school's "Jewish problem."
Today, one argument in support of legacy admissions is that alumni will be more inclined to donate if their kids attend their alma mater. But that claim has been proven false.
When seven colleges stopped accounting for legacy status during the admissions process between 1998 and 2008, there was "no short-term measurable reduction in alumni giving," Chad Coffman wrote in his book, "Affirmative Action for the Rich," as the Washington Post reports.
Prioritizing legacies crowds out applicants from lower-income backgrounds who arguably have a greater need for what elite schools offer: a great education, connections and resources, such as tuition scholarships and grants for unpaid internships.
Low-income students are already vastly underrepresented at these institutions. At Ivy League schools, an average of just 16 percent of undergraduates receive federal aid in the form of a Pell Grant, which is specifically designated for low-income families, the Boston Globe reports. However, nationally, a full 40 percent of undergraduate students receive Pell grants.
Legacy students tend to be wealthy and white, two demographics that are already disproportionately represented at many colleges, especially the most selective ones. Yet those schools can afford to admit more lower-income students, a study from the Georgetown University Center on Education and Workforce points out.
When high achievers from the working class to go to an elite school, it gives them a better chance of graduating and joining the middle or upper class, the study says. Allowing more of them that opportunity would "go a long way toward advancing equity in this country — by giving students in poor financial circumstances a far greater chance of succeeding."
Elite institutions such as Harvard and Yale have increased their share of low-income students in recent years. In 2016, 30 institutions, including all the Ivy League schools, signed the American Talent Initiative, which "aims to attract, enroll and graduate an additional 50,000 lower-income students" by 2025.
That's heartening, given that America's current outdated system of giving preference to the relatives of former students is essentially cheating, says Richard V. Reeves, author of the book "Dream Hoarders" and a senior fellow in Economic Studies and director of the Future of the Middle Class Initiative at the Brookings Institute.
"To operate a hereditary principle in college admissions," he tells CNBC Make It, is unfair. Especially for a country that tells itself it is a meritocracy.
Reeves went to Oxford but, he says, that didn't ensure his son's admission.
When his son applied, "he didn't get in, and it would have been seen as preposterously unfair" if his son had been admitted simply because his father is an alum, Reeves says. "So we might have a hereditary monarchy [in the U.K.], but, by the way, [the members of that monarchy] don't get to go to Oxford and Cambridge anymore, either, because they don't get good enough grades."
That kind of preference for legacy admissions in the U.K. "disappeared in the twentieth century," he says.
By contrast, "the way we organize our education system" in the U.S., he says, "excludes many of those in the bottom 80%." The system is "destroying the American Dream, rather than living it."
This is an updated version of a previously published article.
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