This was part of a larger dream, which I don't remember. At some point, I was in the garage of my mom's old house with my boyfriend, B. We were just hanging around when we heard and saw someone hobble past on a crutch. This person was dressed in rags and was clearly injured very badly, with one foot/ankle wrapped in a very bloody bandage.
Somehow I knew that this was a victim or combatant in the Civil War (i.e. the American Civil War...don't ask me how that got mixed up in my dream), and that this person was a minority of some kind. Not black or white or anything, but more like an ethnic minority of Eastern Europe or something. Anyway, I realized that this guy (it was a young guy) had been gravely injured and was fleeing from combat. He looked just like you'd imagine an Ethiopian refugee might look on TV.
He hobbled past our door and didn't say anything to us, but we could tell he stopped just past the door, because he was making these moaning and whimpering sounds. We didn't know what to do because we could see when he walked by that his whole foot was nearly off, just sort of dangling by the tendon at the heel. You could see daylight through the ankle. And I think he was injured in other ways too.
Eventually he ended up inside the garage, where he started begging us to kill him because he was in so much pain and we couldn't do anything for his injuries. His hair was shaved close and he had huge eyes. He kept asking us to kill him, and crying.
Finally, I went to the garage shelf and got my revolver (??), went over to him and, before I could lose my nerve, I shot him in the head. He died immediately, and I felt kind of relieved for him. But then it occurred to us that it might not be viewed as a mercy killing by anyone else, including the law. We started trying to think of what to do with his body. We were going to bury it in the field, but there was a guy (from my workplace, oddly) out there making dry ice (??) right where we wanted to bury the body.
I was starting to get really upset when I woke up feeling very relieved that I didn't just kill someone.