The movement for minimum wages was first motivated as a way to stop the exploitation of workers in sweatshops, by employers who were thought to have unfair bargaining power over them. Over time, minimum wages came to be seen as a way to help lower-income families. Modern national laws enforcing compulsory union membership which prescribed minimum wages for their members were first passed in New Zealand and Australia in the 1890s. Although minimum wage laws are now in effect in many jurisdictions, differences of opinion exist about the benefits and drawbacks of a minimum wage.