There is another discussion thread about how PIQ’s are evaluated if interested:
I do know the following:
-The number of times the PIQ essays are read are now at the discretion of each UC campus.
-Outside readers are not given access to the whole UC application so race/ethnicity/demographics etc… are not seen.
-The UC uses a consistent system, so all campuses grade on the same scale.
-All readers are required to go through Anti-Bias training.
Based on the Hout report , after the scoring by the 2-3 readers, applications are ranked by score within admission buckets (division or major where admission to division or major is used). For each bucket, a cutoff is set to target a matriculating class size based on estimated yield (which is presumably lower for the top-scoring applicants and higher for those scoring not as well). If the cutoff is within a given score level, a tie-breaking process is used within that score level.
Regarding the comment about Native American ancestry. My understanding is that to claim Native American ancestry on any college application you have to show proof of tribal registry. Especially since the UC’s offer this program: Native American Opportunity Plan | UC Admissions