When measures are taken that would have made an earlier injury or harm less likely to occur, evidence of the subsequent measures is not admissible to prove:
But the court may admit this evidence for another purpose, such as impeachment or - if disputed - proving ownership, control, or the feasibility of precautionary measures.
W.va. R. Evid. 407
COMMENT ON RULE 407
Rule 407 was taken verbatim from the federal counterpart. In addition to stylistic changes, the rule makes two substantive changes. First, the words "injury or harm," found in the first sentence of the rule, were substituted for the word "event" in line 3 of the current state rule. Second, the rule has two new express grounds for exclusion: "a defect in a product or its design" and "a need for a warning or instruction."