Couples have been marrying in some counties since Friday, when a federal judge declared Wisconsin's ban on same-sex marriage unconstitutional.
U.S. District Judge Barbara Crabb in Madison did not issue an order for counties to let couples begin marrying, however. Instead, she said she wanted the ACLU to draft an order for her spelling out how the organization wants her decision implemented.
The ACLU said late Monday that it had submitted its proposal to Crabb. Its proposal would require state officials to let gay couples marry and to recognize gay marriages performed in other states.
The next likely step is for Crabb to hold a hearing on the proposal.