Terrance Tomkow in his own excellent blog:
You are travelling to a lawless third world country to do good works. You make preparation for your journey: You get the appropriate shots. You increase your health insurance in case the shots don't work. To protect the family you are leaving behind, you increase your life insurance and add a double indemnity clause.
Friends advise you to arm yourself, but you are not comfortable with guns. Instead, you visit the office of a private security agency (“The Agency”) to investigate the possibility of hiring bodyguards. The Agency's sales rep explains to you that because of the prevalence of violence and the total absence of law in this country the demand for private security there is high and so the service is very expensive. Looking at their rate sheet you realize it is far more costly than you can afford. As you rise to leave, the sympathetic rep offers you a brochure for one of The Agency's other services. They call it “Revenge Insurance”.
The brochure explains that Revenge Insurance does not provide any protection to its policy holders. However, in the event that a subscriber is the victim of wrongful injury while in-country, the agency will undertake to use its considerable resources to track down the wrongdoer. When they find him, The Agency's operatives will not try to have the wrongdoer pay the policy holder compensation or recover stolen goods. That is a separate service and, given the general poverty in the country, rarely worth the cost. But, if you have Revenge Insurance, what the agency will do to the bad guy who injured you is hurt him.
Question: Is it morally permissible for you to buy Revenge Insurance?