Wis. Stat. § 940.42
Except as provided in s. 940.43, whoever knowingly and maliciously prevents or dissuades, or who attempts to so prevent or dissuade any witness from attending or giving testimony at any trial, proceeding or inquiry authorized by law, is guilty of a Class A misdemeanor.
Wis. Stat. § 940.42
When a mother and child were to testify against the defendant and the defendant sent letters to the mother urging that she and the child not testify, regardless of whether the letters were addressed to the child or the child was aware of the letter's contents, the defendant attempted to dissuade the child through her mother. As the mother of the minor child, had the parental responsibility and practical authority to monitor communications by third parties with the child, and to influence whether the child cooperated with the court proceedings, there was sufficient evidence to convict. State v. Moore, 2006 WI App 61, 292 Wis. 2d 101, 713 N.W.2d 131, 04-3227. This section supports charging a person with a separate count for each letter sent, and each other act performed, for the purpose of attempting to dissuade any witness from attending or giving testimony at a court proceeding or trial. State v. Moore, 2006 WI App 61, 292 Wis. 2d 101, 713 N.W.2d 131, 04-3227.