LOS ANGELES (AP) — Drivers for app-based ride-hailing and delivery services are suing to overturn a California ballot initiative that makes them independent contractors instead of employees eligible for benefits and job protections.

The lawsuit filed Tuesday in the California Supreme Court said Proposition 22 is unconstitutional because it limits the power of the Legislature to grant workers the right to organize and excludes drivers from being eligible for workers’ compensation.

The measure passed in November was the most expensive in state history.

Messages seeking comment from Uber and Lyft, the main supporters of the measure, were not immediately returned.