An Oconto Falls teacher named in a federal lawsuit alleging rampant sexual misconduct among staff in the district has surrendered his teaching license with the Wisconsin Department of Public Instruction.
David Heisel, a technology education teacher, voluntarily surrendered his license March 31.
With Disparti Law Group leading the case, six plaintiffs filed a lawsuit against the Oconto Falls School Board in March.
Amanda Watzka, one of the original three plaintiffs, claimed she was groomed and sexually assaulted by Heisel over three years while at least a dozen colleagues and administrators observed their relationship and said nothing.
No criminal charges have been filed against Heisel.
The lawsuit alleges that in fall 2025 and early 2026, the plaintiffs discovered for the first time that at least 12 teachers and staff members had engaged in grooming, sexual abuse or both with at least 20 identified victims spanning at least 35 years (1988-2025).
The plaintiffs also claim the board had responded to student-on-student sexual assault reports by dismissing victims and taking no corrective action; and the board had received substantial evidence of sexual harassment of female staff members, and that the same staff member was sexting with a student, and the board responded by promoting the individual; and the board had systematically discredited, shamed, silenced or threatened students and parents who came forward.
“This case is about driving meaningful reform and making our schools safer for every student who walks through their doors,” the law firm said in a news release. “We are encouraged that David Heisel has surrendered his teaching license in the state of Wisconsin, but this is only the beginning. More must be done to ensure our schools are truly safe.”
Heisel has held a teaching license since 2002, switching to a lifetime teaching license when it was created in 2017.
He resigned from the district at the end of the 2024-25 school year.
State Sen. Eric Wimberger (R-Gillett) encouraged the DPI to continue its investigation into allegations of grooming and sexual assault in the Oconto Falls School District, including against Heisel.
“The highest responsibility of any education official is to ensure our children are safe at school, especially from predators disguising themselves as authority figures,” Wimberger said. “Ending the Heisel investigation early will not only betray the public’s trust but deny the chance of restoring accountability for the victims who came forward.”
The DPI’s policy is to terminate investigations into allegations of sexual misconduct by teachers as part of a settlement when the teacher voluntarily surrenders his or her teaching license.
“I am calling on DPI to continue investigating the Oconto Falls situation, even after David Heisel surrendered his license,” Wimberger said. “These allegations deserve a full and proper examination so our community can transparently know what happened, when it happened and who knew about the misconduct occurring in our schools.”
A letter to the community on the homepage of the Oconto Falls School District, while expressing support for anyone who has been victimized, reminds residents that allegations are not necessarily factually accurate.
“Additionally, one must consider the reputation of the attorney making those allegations,” the letter states, in reference to Cass Casper, Disparti’s lead counsel in the lawsuit.
In March 2023, the Illinois Supreme Court suspended Casper for engaging in professional misconduct by violating state ethics laws.
According to the Illinois State Bar Association, Casper was suspended for one year and until further order of the Court, with the suspension stayed after 60 days by a two-year period of probation with conditions.
While representing a group of employees in a federal civil rights lawsuit against the city of Chicago and various individual defendants, Casper called one of the defendants whom he knew to be represented by counsel and had an approximately 20-minute conversation about the case.
He later falsely stated to that defendant’s counsel that he made no such call, altered his cell phone records to make it appear as though he did not make the call and sent those altered records to the defendant’s attorney. He also filed the altered records, along with a sworn declaration falsely claiming that they were accurate, with the court.
kpasson@newmedia-wi.com
