Wis. Stat. § 23.99: Parties to a violation.

(1) Whoever is concerned in the commission of a violation of this chapter for which a forfeiture is imposed is a principal and may be charged with and convicted of the violation although he or she did not directly commit it and although the person who directly committed it has not been convicted of the violation.

(2) A person is concerned in the commission of the violation if the person:

(a) Directly commits the violation;

(b) Aids and abets the commission of it; or

(c) Is a party to a conspiracy with another to commit it or advises, hires or counsels or otherwise procures another to commit it.