No officer or member of any association or organization, and no association or organization participating or interested in a labor dispute may be held responsible or liable in any civil action at law or suit in equity, or in any criminal prosecution, for the unlawful acts of individual officers, members, or agents, except upon proof by a preponderance of the evidence and without the aid of any presumptions of law or fact of all of the following:
Wis. Stat. § 103.54