What to do about psychopaths in the workplace?

As a first point, the managers I've known in recent years have overwhelmingly been decent, considerate people in their actions towards me, others, and their workforces. Nevertheless, I am aware that not all are in such a fortunate position, so . . . what to do about psychopaths in the workplace? 

As I'm time limited today, I'm just going to jump straight to my suggestion - I may come back later and add more explanation. 

The solution, in my view, is supporting more activist shareholders - those people who use their influence to drive changes for the better on the climate crisis, the environment generally, modern human slavery - and inclusion and diversity. 

Their influence is limited to their shareholding, so to aid them, I would consider supporting a crowd sourcing campaign, or possibly buying informal "shares" with them. 

The money I give them would be to enable them to buy more shares, so they have more clout. 

The problem, of course, is knowing whether the activist shareholder will do what I consider correct. 

This, by the way, is a good argument for more staff-owned companies: psychopaths find it harder to hide in that environment, although - going by my experience from a long time ago - it can be done.