This article from the Harvard Business Review shines a light on the benefit of a short term (less than 5 years) application of 360 degree feedback, a series of vertical, horizontal, internal and external reviews, as a great levelling tool.

My experience is that managers who like to isolate certain staff members are not fully supported by all stakeholders, and they are repeat offenders. 360 degree review allows these biases to be seen. What it does need is policy on how to correct systemic (institutionalised) negative behaviour. This part is not addressed.

Culturally we sit in an abyss of looking the other way, leaving the perpetrators in place while compensating them or worse, dismissing the victim, as if we cannot do better. There is always an alternative.

I see the need to improve the systemic / institutionalisation of bullying and mobbing until it is no longer possible. All ideas are invited.

https://hbr.org/2001/01/getting-360-degree-feedback-right