Look, if we're talking about assumptions, we're talking about probability. I have no idea who you're talking about. I'll happen upon some statistics once in a while, but otherwise will avoid making assumptions because I simply
don't know. You asked me for what I'd say was most statistically probable, you got it.
I assume you mean "PCP" and not what circuit boards are printed on, yeah. You're right, I've never heard of a rich person taking PCP (cocaine, fancy liquor, etc. for them, right?) although I'm absolutely unsure of how PCP use breaks down racially. (If you have any source for those statistics, you've piqued my interest in them and I'd love a link)
Again, my guess of "white" was based on the fact that most people are white, and thus most cases of violence (without further stratification) are probably by whites. And what, do African-Americans not get community service? That probably wouldn't have changed my mind, and actually sounds a little bit racist.