A group of students and community organizations filed a much-anticipated lawsuit against the University of California, alleging that the university system discriminates against low-income students, racial minorities and others by requiring SAT or ACT admissions tests.

The suit was filed Tuesday in California state court on behalf of a high-school sophomore, two seniors, and a first-year student at Pasadena City College, all of whom it says would be strong candidates for more selective UC campuses except for their test scores. Several California college-prep and social-justice nonprofits are also plaintiffs in the suit. The Compton Unified School District is preparing to file a related suit.

They seek to bar the UC system from requiring applicants to submit SAT or ACT scores, and from using scores in admission decisions unless it can demonstrate a way of assessing the scores “in a rigorous and meaningful, transparent, nondiscriminatory, and non-stigmatizing manner,” according to the suit.

The plaintiffs are wading into a nationwide debate about meritocracy and fairness in college admissions. Concerns that certain groups get special advantages, because of wealth, race or other factors have come to a head with last year’s trial regarding admissions practices at Harvard University, as well as the more recent admissions cheating scandal that accuses families of having their teens lie about their academic credentials and cheat on the SAT and ACT.

More than 1,000 colleges and universities including the University of Chicago and Colorado College now make test scores optional. They have questioned whether standardized tests offer any more value than high-school performance in predicting college success. Worcester Polytechnic Institute and Loyola University Maryland say applicants who don’t submit scores are more diverse than those who do, and perform at the same level once in college.