§ 428.70.Special Answer Filed By Third-Party Defendant

Section 428.70 spells out California's version of third-party practice, layered on top of the general cross-complaint rules. Subdivision (a) defines the roles: a “third-party plaintiff” is a party facing a cause of action who believes a third person should bear all or part of any resulting liability, and who files a cross-complaint against that third person to say so. The “third-party defendant” is the person named in that cross-complaint as potentially liable to the third-party plaintiff if the third-party plaintiff itself loses on the underlying claim.

Subdivision (b) gives the third-party defendant a distinctive tool: at the time of answering the cross-complaint, the third-party defendant may file, as a separate document, a special answer asserting against the original claimant any defenses that the third-party plaintiff itself has to that original claim. That special answer must be served on both the third-party plaintiff and the person who asserted the original claim.

The practical effect is to let a third-party defendant protect itself even if the third-party plaintiff, for whatever reason, fails to raise a defense it has — the third-party defendant's own financial exposure depends on the outcome of the underlying claim, so the statute lets it step in and assert defenses on the original defendant's behalf.