San Gabriel Valley Tribune story claims surrogates of Judy Chu lobbied the redistricting commission to create a more favorable district for her.
The problem with this story (mostly written by someone from the San Francisco Bay Area) is that it rests on the premise that Rosemead is Chu's power base. This sort of strikes me as an "all your bases are belong to us"sort of reasoning. Rosemead isn't big enough or wealthy enough to be anyone's base. It IS Asian, but the desire for an Asian-plurality congressional district extended beyond Representative Chu's office. Also, earlier draft of a Chu district were far more Asian (and politically friendly) to her than the district she wound up with.
The story also implies that (literally) poor South El Monte got shafted, stuck into a wealthy, non-Latino district. However, the new district that includes southern South El Monte is 61% Latino, and the difference in median household income between Rosemead and South El Monte is less than $800/year. They're pretty much the same, economically.
They're trying to make a story out of nothing.