Image caption Abigail Fisher challenged the University of Texas, which had updated its admissions policy after a 2003 Supreme Court ruling

The US Supreme Court has challenged the consideration of a student's race in public university admissions policies.

The court heard an appeal brought by a white student denied a place at the University of Texas in 2008.

A ruling for Abigail Fisher could affect so-called affirmative action programmes elsewhere, analysts say.

The Supreme Court upheld the use of race in admissions in a 2003 ruling, but the court has become more conservative in the past nine years.

Justice Sandra Day O'Connor, who wrote the decision on the 2003 University of Michigan case, has since retired.

Her successor, Samuel Alito, opposes the use of racial preferences in admissions.

'Race above all'?

Justice Alito and Chief Justice John Roberts asked probing questions about details of the University of Texas admissions policy and when race could become a deciding factor between otherwise similar applicants.

The chief justice also asked the university's lawyers how judges would be able to tell when the college achieved a "critical mass" of diversity on campus.

He added later in the session: "I'm hearing a lot about what it's not. I would like to know what it is."

Justice Anthony Kennedy, often seen as a deciding vote between the court's liberal and conservative justices, has also never voted in favour of racial preference, the Associated Press reports.

"What you're saying is what counts is race above all," Justice Kennedy said on Wednesday.

Liberal justices, including Ruth Bader Ginsburg, Sonia Sotomayor, and Stephen Breyer asked questions that some say suggested support of affirmative action.

Correspondents say that even if the court does not uphold the Texas admissions policy, striking down broader consideration of race in university admissions appeared unlikely.

'Respect equality'

The University of Texas updated its admissions policy after the 2003 Supreme Court ruling to consider race without using quotas.

Students in Texas high schools are automatically admitted to the university if they are in the top 8% of their class in terms of academic achievement.

Image caption People queued up outside the Supreme Court from Tuesday evening to get a seat in the courtroom

The threshold was previously 10% and Ms Fisher's grades did not put her in that category.

Race and other factors can be considered as factors in admissions to any remaining spots - approximately 25% of the annual student intake.

Ms Fisher, along with another woman who has since dropped out of the case, filed a complaint arguing that the university's race-conscious policy violated their civil and constitutional rights.

She was never admitted to the University of Texas and has since graduated from Louisiana State University.

"If any state action should respect racial equality, it is university admission," Ms Fisher's lawyers said in their written submission to the court.

A federal appeals court has already backed the University of Texas admissions programme, saying it was allowed under the Supreme Court's Michigan decision.

Justice Elena Kagan, previously involved in the case as US solicitor general, has recused herself from the proceedings.

That leaves eight justices to decide the case, and a 4-4 tie would uphold the decision of the lower appeals court.

Private universities, including elite institutions such as Harvard and Columbia, have filed briefs to the court arguing that their national recruitment policies make it impossible for them to assure diversity without legal backing for racial preference, Reuters reports.