Step 5: Effective investigation

An effective investigation may include any or all of the following:

Interviewing current and ex-employees of the company. It may also be necessary to interview people unrelated to the workplace, if they are able to assist with the investigation.
Verifying all allegations and counter allegations.
In the event both parties present plausible explanations concerning the allegations, making a decision based on the most probable account of events.
Standing down on pay one or both parties during the investigation if necessary.