Restaurants (and other businesses) sometimes post signs stating that they reserve the right to refuse service to anyone. But Title VII of the Civil Rights Act of 1964 prohibits discrimination based on race, color, sex, religion, or national origin and the Americans with Disabilities Act (ADA) prohibits discrimination by places of public accommodation (including restaurants) on the basis of disability.
In addition to these federal statutes that prohibit discrimination against protected classes of persons, some states and cities have laws that prohibit discrimination based on other classifications—such as sexual orientation.
Restaurants have the right to exclude or refuse to serve persons that fail to meet a dress code, for example (“No shoes, no shirt, no service”) or are disruptive, for example, but they do not have the right to exclude or discriminate against persons based on being part of a class or group of persons protected by federal law or by state or local laws.
In Wisconsin, restaurants and other businesses have the right to refuse service to individuals under certain circumstances, but this right is limited by federal and state anti-discrimination laws. Under Title VII of the Civil Rights Act of 1964, businesses cannot refuse service based on race, color, religion, sex, or national origin. The Americans with Disabilities Act (ADA) further prohibits discrimination against individuals with disabilities. Wisconsin state law, specifically the Wisconsin Fair Employment Act, also prohibits discrimination in public accommodations based on protected characteristics, which include but are not limited to ancestry, sexual orientation, and marital status. While businesses can enforce dress codes or refuse service to individuals who are disruptive or pose a health or safety risk, they cannot legally refuse service based on a customer's membership in a protected class.