A lawsuit has challenged the use of race as a factor in Harvard admissions -- a decades-old push to boost minority enrollments at America's oldest and perhaps most prestigious university.

Federal Judge Allison Dale Burroughs heard opening arguments Monday in the non-jury civil trial in Boston, which is expected to last three weeks.

Harvard denies discriminating against Asians but defends its use of broader selection criteria than academic excellence, such as personality, to form a diverse student body.

The university also notes that the proportion of students of Asian origin has increased substantially since 2010, and today account for 23 percent of the 2,000 students admitted to the freshman class, compared to 15 percent blacks and 12 percent Hispanics, out of 40,000 applicants.

Pitted against it is an organization called "Students for Fair Admissions," led by a conservative white activist, Edward Blum, who previously attacked the "affirmative action" policies at the University of Texas.

The US Supreme Court decided against him in 2016, upholding the university's admissions policy.

In Monday's opening arguments, the group's lawyer Adam Mortara claimed that Harvard had used personality criteria to suppress Asian admissions in favor of black, Hispanic and white applicants.

Harvard "let the wolf of racial bias in through the front door," the Boston Globe quoted him as saying.

Bill Lee, the university's lawyer, argued however that "Harvard cannot achieve its educational goals without considering race."

Race is never a negative in admissions, he said.

The Trump administration has weighed in in favor of Blum's suit, asserting that Harvard engages in "racial balancing" in its admissions process at the expense of students of Asian origin.

Whatever the outcome, analysts expect this ultra-sensitive case to wind up before the Supreme Court, where a conservative majority has been solidified with the addition of Trump nominee Brett Kavanaugh.

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