Darden Restaurants Inc., the company that owns Olive Garden, Red Lobster and other restaurants has been threatened with legal action by a workers group claiming that it discriminates against people of of color.

Restaurant Opportunities Centers United (ROC) is an organization that advocates for better wages and working conditions for food industry workers. They have announced plans to file suit against Darden on behalf of behalf Capital Grille employees in Chicago, New York City and Washington, D.C., who claim preference in restaurant hiring was based on race.

The Capital Grille workers, who are ROC members, said that people of color are often relegated to lower paying “back-of-the house” positions as dishwashers and cooks while white workers were given jobs as bartenders and waiters, where they are paid more. ROC also claims that Capital Grille employees were made to work without pay and denied breaks.

“If they have something specific, we want to look into it,” said Darden spokesman Rich Jeffers in a statement to Reuters. Jeffers claims that ROC has provided no details for the allegations against Darden. He said, “Darden Restaurants is very proud of the work environment that it creates for employees.”

Civil rights group ColorOfChange joined ROC in its action against Darden with a petition asking the company to institute a promotions policy that will allow black workers to advance to high-paid positions at its Capital Grille restaurants.

“Black workers are discriminated against throughout the restaurant industry, said ColorOfChange Executive Director Rashad Robinson in a press release. “They are routinely told that they don’t have the right look for the waitstaff and bartender jobs at the fine dining restaurants that pay good wages.”

More than 45,000 ColorOfChange members had signed a petition in the three days after the campaign launched.

Follow Donovan X. Ramsey on Twitter at @idxr