WPI 30.18 Previous Infirm Condition

Use bracketed material as applicable. When liability is directed or admitted, omit the first bracketed phrase.

Use this instruction for a pre-existing condition that was not causing pain or disability. If the pre-existing condition was painful or disabling before the event on which the claim is based, use WPI 30.17 (Aggravation of Pre-Existing Condition). When the evidence is disputed as to the existence of such pre-existing pain or disability, use both instructions.

If the pre-existing condition was a susceptibility that caused more serious consequences, rather than a dormant condition lighted up by the occurrence, use WPI 30.18.01 (Particular Susceptibility).

Use the last bracketed sentence only if the evidence would support a finding that some of the resulting injury would have resulted from natural progression of the condition even without the occurrence.

Do not use this instruction as an insert in the damage instruction. It is intended as a separate explanatory instruction if the evidence warrants it.

This instruction deals with proximate cause. It does not define a separate element of damage, but it is placed here for convenience. In previous editions, WPI 30.18 also dealt with injuries sustained by reason of a person's particular susceptibility, in traditional parlance, the “eggshell plaintiff.” For clarity and better comprehension, the susceptibility concept is now set forth as a separate instruction, WPI 30.18.01 (Particular Susceptibility).

If there is no evidence that a pre-existing bodily condition was causing pain or disability before the occurrence, then the defendant is liable for the aggravation of that condition as well as other damages proximately caused to the person in that condition. See Bennett v. Messick, 76 Wn.2d 474, 478–79, 457 P.2d 609 (1969); Greenwood v. Olympic, Inc., 51 Wn.2d 18, 23, 315 P.2d 295 (1957); Reeder v. Sears, Roebuck & Co., 41 Wn.2d 550, 556–57, 250 P.2d 518 (1952).

The last sentence of this instruction was cited with approval in Hoskins v. Reich, 142 Wn.App. 557, 174 P.3d 1250 (2008). The court stated that “this sentence should only be used ‘if the evidence would support a finding that some of the resulting injury would have resulted from natural progression of the condition even without the occurrence.’” Hoskins, 142 Wn.App. at 568 n.6 (quoting WPI 30.18).

For additional discussion, see the Comment to WPI 30.17 (Aggravation of Pre-Existing Condition).