It's not totally clear what happened from what you've written. For example, I'm not sure what you mean by a "false complaint." However, the general rule is that an employer can't retaliate against employee that reports a problem or lodges a complaint with his/her supervisor or the HR Department. In this context, retaliation refers to the employer taking an "adverse employment action" against the employee. In other words, the employer fires, demotes, or cuts the employee's pay because of the complaint. If that's the case in this situation, then I suggest you contact an employment attorney as soon as possible to discuss the facts of the case in detail and determine whether or not you should file a claim with the EEOC or Wisconsin Department of Workforce Development.
On the other hand - and maybe I'm misreading what you've written here - if you have filed a "false complaint" or a fabricated complaint to your employer alleging some kind of misconduct that did not happen, then your employer would likely have grounds to terminate your employment.
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It is unclear from your question if you are the one terminated or if you're asking about someone else being terminated--it also sounds like you're saying you made a false complaint to HR, so I'm confused. So I will speak in the general: Get a consultation with a local plaintiff employment lawyer. Most give free consultations (check beforehand) so you'd have nothing to lose for an assessment of your case by an expert. You can give that person all the detail for assessment. Aside from this site, your local bar association is also a good referral point. Many such lawyers take the case on contingency if they want to represent you.
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