28 U.S.C. App. (FEDERAL RULES OF EVIDENCE) Rule 407

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: • negligence; • culpable conduct; • a defect in a product or its design; or • a need for a warning or instruction. 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.