(CN) - A case where the driver of a party bus assaulted his passenger needs the California Supreme Court to settle an insurance issue, the Ninth Circuit said Monday.
It has been 7 ½ years since Lillian Gradillas, her husband at the time and others took a party bus around San Francisco.
At the second stop of the night, bouncers at Kelly's Mission Rock denied Gradillas and another woman entrance because they did not have ID.
The two women returned to the bus, which driver Gustavo Rosales then guided to a dark parking lot away from the bar.
Gradillas claimed that Rosales raped her repeatedly when the other woman used the bathroom, with Rosales' nephew guarding the bathroom door.
Gustavo eventually pleaded guilty to felony sexual assault.
Gradillas meanwhile sued American Bus Lines and its owner Kenneth Nwadike, who unsuccessfully tried to rely on his policy with Lincoln General Insurance to defend him.
When Nwadike later stipulated to an entry of $2.5 million judgment, Gradillas and her husband sued Lincoln to enforce that award.
Lincoln appealed to the Ninth Circuit after U.S. District Judge Charles Breyer ruled that it had breached its duty to defend because the injuries resulted from the "use of" the bus.
Tasked with deciding whether the injuries arose from the use of the party bus such that Lincoln had a duty to defend, the Ninth Circuit said Monday that it is unclear under California law which test to use.
Unclear to the court, it said, is whether the vehicle was a "substantial factor" in causing the injuries or whether there was a "minimal causal connection" between the vehicle and the injury.
"Although a series of California Court of Appeal decisions has adopted or recognized the 'predominating cause/substantial factor' test, we note that these decisions are in potential conflict with the California Supreme Court's instruction that the 'vehicle need not be, in the legal sense, a proximate cause of the injury,'" the panel said. Determining which test to apply in the context of this case "will have a significant impact on these and similarly-situated parties," the panel added.
The specific question certified to the California Supreme Court on Monday asks: "When determining whether an injury arises out of the 'use' of a vehicle for purposes of determining coverage under an automobile insurance policy and an insurance company's duty to defend, is the appropriate test whether the vehicle was a 'predominating cause/substantial factor' or whether there was a 'minimal causal connection' between the vehicle and the injury?"
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