I really, really don't think this is a death penalty case. Even if the ultimate charge is Murder one, which I have my doubts about I don't think they would likely pursue the DP. There have just been too many lies and the son who admits to having been armed admit that they went looking for the suspect.
That doesn't mean he gets off, IMO, but I think it is highly unlikely this will end up as murder one. With all the lies and half truths it may end up far less than this.
I noticed yesterday that our local talk radio is now referring to this as a "drug-related" shooting. Now, I realize that doesn't make it true, and I also realize talk radio has a much lower standard of facts than Network TV or print media, but I think it speaks volumes about the public perceptions in this case. Less than a week ago, these same hosts were scolding everyone that was questioning the poor victims.
Any DA, anywhere, has to consider public perception, since it is the "public" in the form of jurors that will decide.