Dr. A is a very evil man who harms millions of people in other countries. In fact, thousands or millions of people die each year because of him. Let's say he's a mad scientist who produces some fraudulent drug that kills people.
Citizen B decides to put a stop to the madness and kills Dr. A.
It isn't a revenge killing; he acts calmly and rationally. And there's no politics involved; they're both civilians.
Are there any notable philosophers who would consider Citizen B just as evil or immoral as Dr. A? If so, what logic would they use to arrive at that conclusion?
I should emphasize that I'm not interested in religious/theological opinions (e.g. "because the Bible says so"). I'm strictly interested in philosophical arguments that can be backed up with some kind of logic.
NOTE: I just read the Absolute Ethics discussion. I'm not sure if it answers my question or not. It kind of sounds like a religious argument to me in that it appears to based more on faith than logic. It sounds like Immanuel Kant is a notable philosopher who might consider Citizen B just as evil as Dr. A, but I'm not sure about his logic.
So I think I'll select leroy's response as the correct answer. To put it in better perspective, it sounds like this would be a better complete response:
Notable philosophical doctrines that would treat Dr. A and Citizen B as equally evil are probably limited to "faith-based" paradigms - e.g. religion and, arguably, absolute ethics.