There are some thresholds that just shouldn’t be crossed. They are like tripwires that you can't see but, when you cross, it will take you down. One such threshold is that of ethics. Once someone crosses an ethical line, in my opinion, they should be jettisoned.
I have a client who hired a marketing and sales director away from a competitor. His first week on the job, he produced “intelligence” in the form of confidential information from his previous employer. In my opinion, he crossed the threshold and should have been terminated. Instead, the employer told the new employee in clear and unequivocal language to get rid of that information and not use it. They saw this as an intermediate but effective step, rather than the Draconian step of termination.
During the course of the next two years, this individual did many things that were ethically questionable, like playing favorites with some of the staff and undermining others who were not his favorites. There were also things that this individual had done that caused his supervisors to finally decide to get rid of him.
In the end, he sensed that he might be fired and did a clandestine data dump. Basically, he downloaded a large quantity of confidential information from his current employer’s database on customers and confidential proprietary information. And then, when the termination came up, he used that information as a weapon to increase his severance package.