SAN FRANCISCO—Companies can be found liable for discrimination against disabled people under state civil rights law even if the discrimination is unintentional, says the California Supreme Court in a decision issued Thursday.

The case involved Kenneth Munson, who has a physical disability that requires the use of a wheelchair, according to the decision in Kenneth Munson vs. Del Taco Inc.

Mr. Munson charged that when he visited the San Bernardino, Calif., restaurant operated by Lake Forest, Calif.-based Del Taco Inc., he “encountered architectural barriers that denied him legally required access to the parking area and rest rooms,” according to the opinion.

Mr. Munson sued the company under the federal Americans with Disabilities Act and California’s Unruh Civil Rights Act. The 9th U.S. Circuit Court of Appeals in San Francisco asked the state Supreme Court to consider the case.

The court agreed with Mr. Munson in its unanimous decision that under the state law, a plaintiff “may obtain statutory damages on proof of an ADA access violation without the need to demonstrate additionally that the discrimination was intentional.”

After a federal district court ruling that had granted partial summary judgment in favor of Mr. Munson, the parties had agreed Mr. Munson would receive $12,000 in damages under the state law, pending an appeal.