Codefendants who cooperate with one another to share costs and protect common interests do not waive the attorney work-product privilege, an appellate court ruled Wednesday. The decision resulted in the disqualification of a plaintiffs firm that hired a lawyer who previously represented one of 17 defendants in a toxic tort case.

The unanimous opinion, authored by 2nd District Court of Appeal Justice Patti Kitching, clarifies key principles of client confidentiality in California and was hailed by one legal ethics expert.