One in two blue-collar workers in the US is an immigrant. Many work in restaurants, nail salons or supermarkets. They’re meant to earn the minimum wage, which is currently $7.25. But employers often pay them far less, or not at all.In the state of New York, the Department of Labor has been working to tighten controls to prevent the exploitation of migrants. But many immigrants are too scared to denounce their employers to the authorities. New York is piloting the Wage Watch scheme, based on the Neighborhood Watch initiative. Groups of people in local communities work with the labor department to improve labor law compliance.