Kansas City, Mo. ? The American Civil Liberties Union has asked a court to overturn the state Department of Social Services’ decision to deny a woman’s application for a foster parent license because she is a lesbian.

The ACLU on Thursday filed a motion for judgment in Jackson County Circuit Court.

At issue is an unwritten state policy that prevents people who are openly gay from becoming foster parents. The ACLU says that policy is the only reason the state would not allow Lisa Johnston to become a foster parent.

Johnston, who has a bachelor’s degree in human development and family, with emphasis on child development, is an educational consultant who has worked for an organization that trains foster parents.

Deborah Scott, a spokeswoman for DSS, said the agency had been expecting the filing. She said DSS has 30 days to respond. DSS has said that DSS has a long-standing practice not to license as foster parents people who declare themselves to be homosexual.

After the application was turned down, the case went to an administrative hearing, where the decision was upheld.

“Missouri’s anti-gay foster care ban does a huge disservice to children,” Ken Choe, an attorney with the ACLU’s Lesbian and Gay Rights Project, said in a news release. “We hope that once the court sees how arbitrary DSS’s denial of Lisa Johnston’s application was, this decision will be reversed.”