It is no defense to a prosecution for a crime that the victim also was guilty of a crime or was contributorily negligent.
Wis. Stat. § 939.14
A jury instruction that a defrauded party had no duty to investigate fraudulent representations was correct. Lambert v. State, 73 Wis. 2d 590, 243 N.W.2d 524 (1976). This section does not prevent considering the victim's negligence in relation to causation. This section only means that a defendant is not immune from prosecution merely because the victim has been negligent. State v. Lohmeier, 205 Wis. 2d 183, 556 N.W.2d 90 (1996), 94-2187.