Harvard started its defense in federal court today with testimony from an economist and the first black president of an Ivy League school.

The school is being sued by a group called Students For Fair Admissions, which claims Harvard discriminates against Asian-Americans in the applications process.

Last week SFFA called to the stand Peter Arcidiacono, a Duke economist whose analysis of Harvard's admissions process concluded there was bias against Asian-Amerian applicants.

That finding was disputed by David Card, an economics professor at the University of California at Berkeley, who ran his own statistical model that found there was no evidence of discrimination.

During his testimony, Card explained that Arcidiacono's model didn't include students who were athletes, legacies as descendants of alumni, applicants on the dean's interest list or children of faculty or staff, a group referred in court collectively as ALDC.

It also didn't include whether students had interviews with Harvard staff during their admissions process and other variables, including what career they planned on pursuing.

Card also pointed out Harvard's focus on having students who are strong in multiple areas, not just academics. He found that while academic strength is the most common area of strength for applicants, 46 percent of the admitted pool of students are considered to have three or more strengths, like high personal or extracurricular ratings.

He stressed the importance of being a well-rounded, multi-dimensional applicant.

"It really is the defining feature of the admissions process," Card said.

Harvard also called Ruth Simmons, the current president of Prairie View A&M University in Texas. She became the president of Brown University in 2001, making history in the process by becoming the first black president of an Ivy League school.

Simmons, who described the struggles of growing up in the segregated South as a child, defended diversity on campus, saying the benefits flow to students, institutions and society.

Simmons, who received her master's and PhD from Harvard, said the benefits of diversity also impact the university's prestige.

"The standing that we enjoy around the world is surely due to our diversity," she said.

Without diversity, she said, the Harvard's mission would be "impoverished."

Simmons also defended the its practice of giving tips in the admissions process to ALDC students.

For example, she said that financial contributions from alumni have made Harvard stronger.

"We’ve been made stronger by benefit of that involvement," she said. "One of the ways that we signal to alumni that is important to us is that we consider their children in the admissions," she said.

She also pointed out that schools like Harvard would never admit students solely on their parents' alumni status or contributions.

Judge Allison Burroughs, who is overseeing the trial, pointed out that the Supreme Court has said schools cannot have maximum quotas or minimum floors for groups of students. She asked Simmons how schools can avoid floors for groups of students when attempting to ensure that there's enough of a diverse population on campus.

Simmons said changes will continue to be constantly made, the process will keep evolving and what works at one institution doesn't necessarily work at another.

“I don’t ever see this at a fixed point where we’re utterly satisfied, as a nation, that we’ve figured this out," she said.

Simmons also described how she believes the benefits of diversity flow not just to the universities, but to society at large as students leave college with the tools to work with people from different backgrounds.

“It’s with great conviction that I say that we must continue to offer diverse undergraduate education to our young people," she said. "To save our nation.”

The trial will continue tomorrow with more of Card's testimony. Lawyers for the plaintiffs have yet to question him.