Donald Trump’s challenge to his criminal hush money case based on the Supreme Court’s recent presidential immunity ruling has alarmed a legal expert who warns the decision’s “manipulability” could imperil his conviction. Legal analyst Lisa Rubin dissected for MSNBC Trump’s filing and the argument that he and the Trump Organization could not be guilty of fraud under the new ruling. “They assert that the Manhattan district attorney’s presentation of evidence included testimony, tweets and even a required government ethics form that are themselves evidence of Trump’s exercise of ‘core’ presidenti…