Wis. Stat. § 904.10: Offer to plead guilty; no contest; withdrawn plea of guilty.

Evidence of a plea of guilty, later withdrawn, or a plea of no contest, or of an offer to the court or prosecuting attorney to plead guilty or no contest to the crime charged or any other crime, or in civil forfeiture actions, is not admissible in any civil or criminal proceeding against the person who made the plea or offer or one liable for the person’s conduct. Evidence of statements made in court or to the prosecuting attorney in connection with any of the foregoing pleas or offers is not admissible.