You're being a bit ambiguous. I would say that in all countries, there exist individuals who in their own subjective opinion would view capital punishment as murder.
But you're not engaging with my point on its own terms, and as such are missing it entirely. In the case of an individual viewing capital punishment as murder requires an ethical judgment to be made, which is the point, not the example.
If an author says "we" and you disagree with them, it is not productive to nitpick about whom that class names: you already have enough information to answer it: a group the author is aware of and identifies with in regard to the following view. You reading it doesn't imply you're a part of the class.
Secondly, the usage of "we" in hypothetical discussion acts more as a fairly neutral stand in to satisfy English's requirement for an explicit subject, while setting the right tone.
But for the sake of precision, as no one is above a tacit request for precision...
If a criminal on death row is executed, one who views capital punishment as ethical would not describe the killing as murder.