I have no desire to wade into a political debate about immigration, as I think it distracts from the real issue which is ensuring justice is served in Gabriel Cuen-Buitimea's death based on the facts.
Right now, all the information we have is either from the prosecution or the defense, both of which want to present the facts to support their point of view. In my experience, especially in cases where a defendant claims self-defense, the truth generally falls somewhere in the middle. Given that, I think it's important to acknowledge that until all facts and evidence are presented it court, we, as members of the public, only have access to the narratives both sides are presenting.
Based on the information which has been made public, my biggest question is whether or not Kelly was justified in feeling like his life was in immediate danger. In other words, would a reasonable person in Kelly's position utilize deadly force to protect himself and his property?
The defense has argued that Kelly fired warning shots. If that is indeed true, I think it casts some doubt on his self-defense argument. From what I can tell, Arizona does not have an explicit stand-your-ground law, so it will ultimately come down to whether or not a jury believes Kelly acted reasonably under the circumstances. IMO I think the prosecution can argue (based on the information we have so far), as has been done elsewhere in other cases, that Kelly's decision to fire a warning shot effectively means he did not feel his life was in immediate danger.