A conservative legal advocacy group has sued the State Bar of Wisconsin, claiming its diversity fellowship program for law students violates the free speech rights of bar members whose dues are used to fund it.

The lawsuit, filed by the Wisconsin Institute for Law & Liberty on Tuesday on behalf of a Wisconsin attorney, is the latest in a series of legal challenges to diversity programs after the U.S. Supreme Court ruled in June that colleges and universities cannot consider race in admissions.

Plaintiff Daniel Suhr claims he should not have to pay for the state bar’s fellowship program because it is unconstitutional and not germane to the core functions of the bar. Using Suhr’s mandatory dues for what he claims is an illegal program violates his First Amendment rights under the U.S. Constitution, the lawsuit said.

The State Bar of Wisconsin will “vigorously defend” the diversity program, executive director Larry Martin said in a statement Wednesday.

“Neither race nor ethnicity is an eligibility factor or requirement for purposes of participation,” Martin said.

According to its website, the diversity fellowship is open to first-year students at Marquette University Law School and the University of Wisconsin Law School who demonstrate a “commitment to diversity” and a record of academic achievement.

Fellows receive 10-week paid summer positions at law firms, corporate legal departments, and government agencies.

The complaint said the State Bar in the fall modified the program criteria with race-neutral language that invites applicants “with backgrounds that have been historically excluded from the legal field.” But the change did not make the program legal, the lawsuit said.

“The program was founded with an intent to discriminate based on race, and that intent continues to shape and govern the program today, as is evident from the program enrollment,” it said.

Suhr asked the court to the enjoin the state bar from “implementing the program in a manner that violates the rights of law students” and from using Suhr’s dues for the program, and to award damages.

A different group founded by anti-affirmative action activist Edward Blum, who brought the Supreme Court affirmative action challenge, earlier this year sued law firms Winston & Strawn, Perkins Coie, and Morrison & Foerster over their diversity fellowship programs.

Blum later dropped all three lawsuits after the firms altered their application criteria.