SALT LAKE CITY — Civil rights advocates are challenging a Utah law that eliminated a requirement that disabled adults whose biological or adoptive parents petition courts to become their legal guardians have their own attorney.

The ACLU of Utah and the law firm Latham & Watkins sued the state in federal court Thursday on behalf of the Disability Law Center and two people identified as Katherine C. and Anthony M.

The law gives judges the final say on whether a potential ward needs legal representation in a guardianship proceeding. It applies only to guardianship petitions filed by biological or adoptive parents and if the potential ward’s assets are less than $20,000.

Members of the state's disability community and the Utah State Bar opposed the bill when the Legislature passed it in 2016. The law is set to expire in July 2018 unless lawmakers renew it when they convene next January.

People with disabilities face unique and serious threats to their freedom and independence when someone seeks legal guardianship over them, said Aaron Kinikini, Disability Law Center legal director.

"We want to ensure that our members have absolutely every legal protection they deserve when going through the guardianship process," he said.

Bill co-sponsor Sen. Lyle Hillyard, R-Logan, said the legislation affects him personally, both as the father of an adult child with disabilities and an attorney.

Many parents in the same circumstance have raised a child with disabilities from birth and have their best interests at heart but need guardianships to continue to help guide their child's medical, legal and financial affairs once they reach adulthood, Hillyard said.

Most of them, he said, can't afford to hire an attorney for themselves and their child.

"That just doesn't make sense to me. I think we get so anxious making sure everybody’s legal rights are protected that we actually price them out of the market," Hillyard said.

He called the law "very, very limited" because it only applies to those whose assets are less than $20,000. In addition, Hillyard said judges can stop the legal proceedings and appoint an attorney for the child if they believe one is needed.

The lawsuit, which names the state, Utah Administrative Office of the Courts and Utah Judicial Council as defendants, demands a right to a lawyer for anyone who is to be put under guardianship.

Plaintiff Katherine C. has schizophrenia and works as a junior law clerk at a Salt Lake nonprofit. She lives with her parents because of her disability, according to the lawsuit.

Anthony M. has developmental and intellectual disabilities. He works as a school custodian, and though he lives with his wife and son, he receives care and financial support from his parents, the lawsuit says.

Both have less than $20,000 in assets and have expressed concerns about losing the right to make important medical and housing decisions for themselves, should their parents gain legal guardianship over them at some time in the future, according to the ACLU.

Once granted, guardianship is rarely if ever revoked, said John Mejia, ACLU of Utah legal director.

"When facing the loss of the right to make deeply personal decisions for themselves for the rest of their lives, people with disabilities need to have unfettered access to legal assistance," he said.