Legal Question in Civil Litigation in California

All communications between an attorney and his/her client is privileged, including invoices. Communication between an attorney and an expert witness is not privileged but some documents exchanged may be protected under attorney work product. Experts are not always unbiased. After all, they are paid for their opinions and can be impeached with proof of bias, etc. But the time to impeach (show loss in credibility) is during a deposition or trial not after testimony is given and you didn't like what was said.

I disagree with two portions of Ms. Karila's answer.

First, a lawyer's communication with an expert witness -- even one who has not been hired yet -- is privileged. Some parts of that privilege may be waived if the lawyer uses the expert's opinion. But unless and until that happens, the communications are privileged. And some of the communications may remain privileged even after the the opinions are divulged.

Second, invoices are not inherently privileged, but they often contain a great deal of privileged information. They must sometimes be produced, but the lawyer and/or client can first redact the privileged portions.

Ms. Karila is right that expert witnesses can be impeached for bias during a deposition and/or at trial. But that does not mean the expert's communications with the lawyer aren't privileged.

I just looked at Ms. Karila's answer again and saw another statement I disagree with. She wrote that all communications between an attorney and client are privileged, but that's only true when the communication is about the subject(s) on which the lawyer is advising or representing the client. The privilege also applies when the client seeks advice about new subjects. Other communications are outside the privilege.

That's why invoices aren't inherently privileged. They communicate how much work was done, what type of work it was, and how much it cost. That information isn't about the subject-matter of the representation. Sometimes the invoice will contain details (like a summary of a phone conversation) that are privileged, but the rest of the document will still not be covered.