The D’Amico v. Board of Medical Examiners (1974) 11 Cal.3d 1 doctrine about summary judgment affidavits not being allowed to contradict admissions in discovery is not a doctrine regarding the admissibility of evidence, but rather whether the contradictory evidence can be given an weight. Here, an expert changed his answer on the key question of whether a plaintiff was exposed to asbestos though he wasn’t present when the work on the asbestos-containing materials was performed. He said no in his deposition, but yes in his declaration. The declaration was admissible and should have been given weight sufficient to preclude summary judgment because the expert explained he had not considered at the deposition whether the asbestos particles could have been re-entrained in the air and thus present when the plaintiff later appeared on the scene. The expert didn’t change his statement of the underlying facts but merely employed a new scientific theory to interpret them.