We still don’t know what exactly went down during President Donald Trump’s trip to Walter Reed National Military Medical Center last week—and, if his trip in 2019 is anything to go by, we never will. NBC News has reported that Trump’s mysterious visit to the hospital last year, which has never been adequately explained, has been subjected to nondisclosure agreements. According to the network, Trump required all medical staff to sign NDAs before they could treat him—and at least two doctors who refused to sign the contracts were not allowed to have any involvement in his care. It’s unclear why the action was taken when federal law already prohibits medical practitioners from disclosing any patient’s personal health information without their consent. It’s also not known i Trump made last week’s care-providers sign the documents.