> No, the company should investigate and have evidence, one way or the other, beyond just the complaint before any kind of final action, though there are some interim precautionary mitigations that are might be appropriate, often.

No, the company isn't equipped for this and this is the role of the police and judicial system.

> “Innocent until proven guilty” is a maxim of criminal law; a company treating potential harassers as if the company were either the state enforcing criminal law or, worse, as if it could act only following the state enforcing criminal law will eventually find itself in quite deep civil liability for harassment.

That's why the company isn't enforcing anything and delegating the task to the competent authorities. In this case the police.

Many people have been victim of wrongful firing and huge damages to their personal life due to rash decisions being taken by companies based on a single complaint from someone.