On Tuesday, groups including the ACLU and the National Employment Law Project, submitted an amicus brief—an advisory legal document containing arguments for courts to consider—to the court considering appeals by Uber and Lyft to overturn an injunction demanding they immediately reclassify their drivers as employees.

The brief argues that gig companies don’t offer “opportunities” for communities of color so much as “deepen the desperation of workers who have been excluded from stable employment,” and that workers of color are “uniquely harmed by the companies’ misclassification.”

Bolstering the first argument is the simple nature of classification: firms misclassify workers who are actually employees as independent contractors to deny them benefits and protections that would otherwise inflate labor costs. In the case of app-based gig companies like Uber and Lyft, the vast majority of work is done by Black and brown workers, but specifically a small core of them who drive full-time. Uber’s own internal data shows that workers of color are overrepresented when compared to the population, reporting that 63 percent of its drivers are non-white. A survey of drivers in San Francisco, one of Uber’s and Lyft’s most important markets, found that 80 percent of their drivers and couriers are people of color.