The government's "Don't Ask, Don't Tell" policy has already been struck down once—by a federal judge in Riverside who ruled the policy, which bars gay and lesbian troops from serving openly, violates the U.S. Constitution. The ruling in the case is now before the 9th U.S. Circuit Court of Appeals.
In San Francisco this morning, another suit was filed to overturn the policy. The grounds are similar: Don't Ask, Don't Tell violates servicemembers' Fourteenth Amendment rights to equal protection and due process and their First Amendment rights of speech and free association.
The wrinkle this time: The new suit was brought on behalf of three servicemembers who were discharged under the policy. They are seeking reinstatement.
Here's a copy of their complaint, a 22-page PDF, filed with the U.S. District Court for Northern California in San Francisco: