The California Supreme Court declined to hear a constitutional challenge to the ballot initiative that allows gig companies to continue classifying drivers as independent contractors.

The lawsuit filed by a handful of drivers and the Service Employees International Union in January claimed that Proposition 22 usurped the power of the Legislature and eliminated its ability to give workers the right to organize or to access the state’s workers’ compensation system, according to a report by the Los Angeles Times.

The high court did not explain its 5-2 decision not to hear the challenge. The court left open the possibility that the lawsuit could be filed in a lower court, but plaintiffs would not say whether they planned to continue pursuing the case, according to a report by the San Francisco Chronicle.

Proposition 22, approved by nearly 59% of voters in November, allows companies such as Uber and Lyft to continue classifying drivers as employees. The companies are required to provide occupational accident insurance in lieu of workers’ compensation. The initiative mandates that accident policies cover up to $1 million in medical expenses and provide temporary disability payments equal to two-thirds of a driver's average weekly earnings.

The initiative does not require permanent disability benefits and does not include any vocational rehabilitation or return-to-work programs that are comparable to what’s available in the work comp system.