What is the test for using a special verdict form in a motor vehicle accident?

Question 16 was included on the special verdict form because Civil Code section 1431.2, subdivision (a), enacted in 1986 as part of Proposition 51, provides as follows: In any action for personal injury, property damage, or wrongful death, based upon principles of comparative fault , the liability of each defendant for non-economic damages shall be several only and shall not be joint. Each defendant shall be liable only for the amount of non-economic damages allocated to that defendant in direct proportion to that defendant's percentage of fault.... (Italics added.) However, such an allocation does not apply to defendants whose liability is vicarious. (Diaz v. Carcamo (2011) 51 Cal.4th 1148, 11561157, 126 Cal.Rptr.3d 443, 253 P.3d 535.)