I see. Thank you for clarifying that for me, Mary.
This sounds like a clear cut case of defamation, an intentional tort, which could be brought against the workers making the false statements about you.
In many cases similar to this, a demand letter from a local attorney can stop them from continuing to engage in this conduct and even motivate them to retract their false and slanderous statements if they wish to avoid a lawsuit. So I would retain a local attorney quickly to do just that. I would look for a local employment law attorney who has experience pursuing tort claims such as this if possible. A civil litigation attorney would also be good at handling this type of situation normally, but it would be best if they had some employment law background as well since this is occurring in the employment context.
Here is a link to a site which sets out the elements of defamation under CA law for your reference:
The state bar association can provide you with attorney referrals. They can be found at calbar.org.
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