How does the concept of Ethics relate to Managerial roles?

If you accept case studies here are a few examples. In one major retailer, the management began using lying as a management technique. The clerks discovered it. They began stealing from the store as if there was no tomorrow. As a result, the company had a loss. In another company, the top level management decided to use pressure on their middle level management. The use of pressure either caused their best middle level managers to have nervous breakdowns or to leave the company. As a result, the company folded.