Hospitals that treat California's poorest patients are faring badly under the Affordable Care Act's drive to improve quality. Under ACA authority, Medicare is imposing fines on safety-net hospitals at twice the rate paid by other hospitals, according to an analysis by the Center for Health Reporting. One local safety-net hospital, Emanuel Medical Center in Turlock, was the most highly penalized in the state. "The safety-net hospitals are dealing with a population that's sicker by the time they show up at the hospital," said Alice Chen, a health economist at the University of Southern California. "This stacks the deck" against them.