Amazon (AMZN+1.45% ) manipulates its workplace injury data and rejected recommendations to improve safety conditions for its workers, according to a Senate investigation into labor rules at the U.S.’s largest online retailer. The 160-report from the Senate Health, Education, Labor, and Pension (HELP) Committee is the result of Sen. Bernie Sanders’ investigation into the company’s “abysmal safety record” that he launched last year. The report says Amazon manipulates workplace injury data to make...