If it was a black area, it would have been mentioned; and since Arroyo Grande is in Mexifornia, chances are the perp is Mexican or of Mexican descent.
We may never know because he is underage, however.
However, since mass school shooters (as opposed to gang type violence) and suicidal kids are more typically disturbed white kids, I guess I was actully picturing a "troubled" white kid who had been bullied a few too many times when reading the article. Thus, your comments caught me off guard. I thought "What the heck is he talking about and why is it important here?" I hadn't even considered the predominantly Hispanic population.
Both genralizations can be made, so I felt "guessing the race" was pointless here. I do it myself, but only if race was the reason for a crime (like black hate crimes again whites, which are never idenitified as such) or if a perp is still on the loose and SHOULD be identified. I also recognize and bristle at the racial reporting with the more rare white on black hate crimes.
Any other situation just seems to have no purpose. Be aware that your comments, whether intended or not, can be construed as an attempt to advance a racist agenda itself and is dangerous. This is why I like to preserve this type of speculation for instances where a greater level of relevance is present.