Francisco Castaneda was an illegal immigrant who got busted on a meth charge and was sent to a federal facility. Unfortunately, Castaneda had penis cancer. Instead of treating him, officials gave him ibuprofen, antibiotics and extra underwear. It took 10 months to get a biopsy, and even after the amputation, it was too late -- the cancer had spread. He died.
His family tried to sue the individual employees who handled Castaneda's case. The U.S. Supreme Court, however, says those people can't be sued as long as they were carrying out their official duties. (Such lawsuits are OK against the government as an entity, though there are caps on damages.)
Hat Tip: Many thanks, Keith G in PV!