A Sonoma County jury may get to decide a case that has far-reaching implications for thousands of in-home caregivers throughout California.

The key issue in a civil lawsuit filed by a local caregiver is who qualifies as her employer -- the client who receives care through the Sonoma County's In-Home Supportive Services program or the county itself, or both.

Adelina Guerrero, a Santa Rosa caregiver whose disabled client apparently absconded with seven months of Guerrero's wages, tried to collect her pay from the county in 2011. She was denied, and a Sonoma County Superior Court judge dismissed most of her legal claims, ruling that the county wasn't responsible because it wasn't her employer.

But last week, a state appeals court reversed that ruling and sent the case back to Sonoma County for a trial. The county can still appeal to the state Supreme Court.

Lawyers for Guerrero said the case could affect every county that administers the in-home care program for low-income or disabled residents and the thousands of workers who provide the care.

"This is a massive problem for IHSS workers," said William Hoerger of California Rural Legal Assistance.

Many of the caregivers, like their clients, are lower income and often are immigrant women who don't understand their legal rights, he said.

Their advocates probably didn't realize, either, he said, that the county or the program set up to administer it could be held responsible as "co-employers."

"This is probably the first case in the state that has been litigated in this way," Hoerger said. "This could really have a large impact."

A county lawyer representing In-Home Supportive Services and Sonoma County couldn't be reached Friday for comment.

According to court papers, Guerrero worked seven days a week over a four-month period in 2008 and 2009 for a recipient of the IHSS program of the county's Human Services Department. She logged 501 hours regular time and almost 87 hours of overtime.

The program is designed to help low-income elderly or the disabled live independently in their own home with a caregiver whose wages are paid through the county's Human Services Department.

But when Guerrero was never paid and her client disappeared, she tried to collect her wages through the county. The county rejected her request for pay.

The county said it wasn't responsible. It had paid the client, who apparently pocketed payments meant for Guerrero, Hoerger said.

Sonoma County Superior Court Judge Elliot Daum threw out most of Guerrero's lawsuit, reasoning that the county wasn't her employer and thus not responsible.

The county argued, and Daum agreed, that the county and IHSS weren't her official employers and that the recipient was the employer and that Guerrero's position was exempt from federal and state minimum-wage and overtime laws.

The county said it doesn't have the power to hire, fire or supervise a caregiver. The recipient does, which makes that person the employer, the county said.

But the appeals court, on a 3-0 decision, disagreed, saying the county and IHSS hold the purse strings and set strict guidelines about the hiring of caregivers. The program also authorizes what kind of care a client can receive, their specific duties and how much time is allowed for each task.

Those factors and others point "strongly toward the existence of an employment relationship between (the county and IHSS) and the provider," the ruling states.

Hearings in the case are set for later this month in Sonoma County court.