That is kind of my point. I was being sincere when I said I was confused by the person I replied to. It seems like they are advocating for less research into the negative/positive effects of the death penalty because those deaths are relatively few.

Alternatively they could be saying all the resources put towards catching murderers since the number of those they murdered are relatively few.

To be clear I'm strongly against the death penalty. OPs comment seemed to trivialize the deaths that happen as a cause of murderers or the actual killing of those murderers and I have an issue with that framing. I think putting resources towards understanding these things are resources well spent since they directly impact what society decides is justice.