Indiana Republican Sen. Mike Braun bashed what he described as "progressive social engineering" on the part of Harvard University, in a letter critiquing the school's penalties for members of single-gender groups.

The senator sent the open letter to Harvard University President Lawrence Bacow earlier in April, urging him to reconsider the school’s policy penalizing students for being part of single-gender organizations, namely sororities and fraternities, The Harvard Crimson reported. Braun is an alumnus of Harvard Business School and was a member of the Phi Delta Theta fraternity during his time as an undergraduate at Wabash College.

“We cannot cure social ills by rejecting the natural human desire to form bonds among single-sex groups"

Campus Reform previously reported on the Harvard policy itself, which prohibits members of single-gender groups from getting scholarships, faculty endorsements for certain fellowships, and holding leadership positions on Harvard sports teams and recognized student groups.

[RELATED: Harvard gets hammered with lawsuits over ‘sexist’ same-sex club policy]

“Federal law recognizes the positive role that such organizations can take at universities,” the senator wrote in his letter. “Indeed, under Title IX, the federal law prohibits gender discrimination in higher education, Congress specifically exempts ‘the membership practices of a social fraternity or social sorority.’”

Braun added that “the university’s decision also raises serious concerns about how far an institution like Harvard will go in its agenda of progressive social engineering,” and concluded his letter stating “we cannot cure social ills by rejecting the natural human desire to form bonds among single-sex groups.”

Braun’s full letter is available on the official website of the “Stand Up to Harvard” campaign.

According to the Harvard Crimson, Braun’s letter came after three Harvard students took part in a fraternity and sorority congressional advocacy event on Capitol Hill. Bacow replied to Braun via a letter sent to his senatorial office, in which he defended the school’s decision regarding single-gender organizations.

“Students may choose to join unrecognized, single-gender social organizations, but the University has chosen to adopt a policy regarding student eligibility for leadership positions in Harvard-recognized organizations or Harvard endorsements that is aligned with our core values of non-discrimination and inclusion.”

In December 2018, when legal cases were filed in both Massachusetts court and federal district court against the Ivy League school, Harvard student Sigma Alpha Epsilon member Conor Healy shared his thoughts on the policy with Campus Reform.

[RELATED: EXCLUSIVE: Harvard frat student says same-sex club policy ‘undermines’ individualism]

“It goes against everything Harvard should stand for, and it goes against what American universities should stand for,” Healy said. “It completely undermines their best trait, which is the ability for students to be individuals and make their own choices and to not be parented.”

Follow the author of this article on Twitter: @VSnitsarUSA