A party may not raise a triable issue of fact on summary judgment by relying on evidence that will not be admissible at trial.  Accordingly, if a party fails to exchange expert witness information in response to a timely demand, and the time to respond expires before the summary judgment motion is filed, the non-responding party may not rely on expert testimony to oppose the summary judgment motion over the moving party’s objection, unless the trial court relieves the non-responding party of its default under CCP 2034.610 or 2034.710.  Mann v. Crachiolo (1985) 38 Cal.3d 18 is overruled, and Kennedy v. Modesto City Hospital (1990) 221 Cal.App.3d 575 is disapproved to the extent they held to the contrary that an excludable expert declaration could raise a triable issue of fact on summary judgment even though inadmissible at trial.

California Supreme Court (Corrigan, J.); February 23, 2017; 2017 WL 712748