First of all, as you just pointed out, the tools exist; they include the police and the services offered by the department. But the immigrant woman's interaction with those services and the police is a sensitive matter. Agencies here would have to explain to immigrant women what the police do. They would need to allay these women's fears and help them understand how things work here, to change their thinking and ideas from back home.
Basically, efforts need to be made at the front end, before these women get here, and once they are here, a lot of outreach and education is needed.