Attorney Cezar Britto says his client will sue for injuries, medical expenses and lost income.
He describes Romilda Aparecida Ferreira as a "sex professional and dancer" who met the Americans at a nightclub on Dec. 29, 2011. She and three other women left with the men in three vehicles.
Britto says that after an argument, a Marine tossed her from the vehicle. She broke her collarbone, two ribs and punctured a lung.
The State Department says the woman was outside, trying to open the moving vehicle's door.
The four Americans were sent home.