A recently unearthed 2009 Ph.D. dissertation approved by Harvard Kennedy School faculty has drawn strong criticism for its assertion that low-IQ individuals—a demographic that the author says is disproportionately Hispanic or of other non-white or non-Asian ethnicities—should be restricted from immigrating to the United States because they lack “raw cognitive ability or intelligence.”

Outrage over the thesis—unearthed by the Washington Post after its author Jason M. Richwine coauthored a paper published by the Heritage Foundation—has led Harvard students to write a petition stating that the Kennedy School “cannot ethically stand behind academic work advocating a national policy of exclusion and advancing an agenda of discrimination.”

The petition, delivered to University President Drew G. Faust and Kennedy School Dean David T. Ellwood earlier this month, garnered the support of 23 Kennedy School student groups and Kennedy School Student Government President Rohit Malhotra.

In an email to the petitioners, Ellwood defended the Kennedy School’s decision to approve the thesis.

”Bad ideas should be pushed out by good ideas, not by censorship,” he wrote.

In an interview with the Boston Globe, Richwine defended his thesis in the name of academic freedom.

“This is a really worrisome idea here, that the students want to dictate what scholarship will be allowed at Harvard University,” Richwine said.

In a statement to The Crimson, Richwine also defended the relevance of his research.

“Right now there are so many powerful interest groups aligned to support low-skill immigration that I doubt any proposal to switch to high-skill immigration (with or without the use of IQ tests) could go very far politically,” he wrote. “But it can’t hurt to talk about it.”

The thesis was brought to public attention when Richwine coauthored a Heritage Foundation paper examining the economic impact of proposals to overhaul the country's immigration laws. Subsequent backlash against the thesis precipitated Richwine’s resignation from the Heritage Foundation earlier this month.

While Kennedy School officials and faculty have countered claims that the dissertation does not meet academic standards, petitioners insist that Richwine’s dissertation committee was ill-prepared to oversee his thesis.

Although professor George Borjas—head of the committee that oversaw Richwine’s research—told Slate magazine the dissertation’s empirical work was sound, he acknowledged that he had not studied the relationship between IQ and immigration.

Richwine told The Crimson, however, that the other members of the faculty committee, Christopher S. Jencks ’58 and Charles A. Murray ’65, are experts in this area.

Ellwood also defended the expertise of the committee, writing that “three intellectually diverse, serious scholars reviewed and accepted the dissertation.”

The review committee aside, some questioned the quality of Richwine’s research.

“Key terms are poorly defined, auxiliary assumptions abound, and the literature I’m familiar with that is cited as authoritative is, well, not good,” wrote Tufts University professor Daniel W. Drezner in a Foreign Policy blog post.

A number of petition signatories read Richwine’s thesis and said they found numerous errors and missteps, which they brought to Ellwood’s attention during a recent meeting, according to Malhotra.

Since the beginning of the controversy, the Heritage Foundation has distanced itself from the former staffer and from his contentious academic work.

“The Harvard paper is not a work product of The Heritage Foundation. Its findings do not reflect the positions of The Heritage Foundation or the conclusions of our study on the cost of amnesty to U.S. taxpayers, as race and ethnicity are not part of Heritage immigration policy recommendations,” wrote Mike Gonzalez, vice president for communications at The Heritage Foundation, in a statement earlier this month.

—Staff writer Maya Jonas-Silver contributed to the reporting of this story.

—Staff writer Steven R. Watros can be reached at watros@college.harvard.edu. Follow him on Twitter @SteveWatros.

This article has been revised to reflect the following clarification and corrections:

CLARIFICATION: May 30, 2013

An earlier version of this article stated that Jason M. Richwine’s controversial dissertation was a Harvard Kennedy School Ph.D. thesis. To clarify, while the thesis was approved by Kennedy School faculty, Richwine's degree was conferred by the Graduate School of Arts and Sciences.

CORRECTIONS: May 30, 2013

Due to an editing error, an earlier version of this article incorrectly stated that the dissertation claimed that Hispanics and other ethnic groups should be restricted from immigrating to the United States. In fact, the thesis claims that people who have low IQs—a demographic that Richwine claims is disproportionately Hispanic or of other non-white or non-Asian ethnicities—should face immigration restrictions. The article also incorrectly stated that Richwine used data from his Harvard dissertation to coauthor a Heritage Foundation paper. In fact, the two papers are unrelated, according to Richwine.