Chaos in the courtroom of former President Donald Trump’s criminal hush money case could provide prosecutors with ample grounds to demand a new trial if the jury deadlocks, former acting solicitor general Neal Katyal told MSNBC’s Ari Melber on Monday. Robert Costello, the former legal adviser to Trump’s former fixer Michael Cohen, took the stand to discredit his former client. But his testimony was derailed when Justice Juan Merchan felt compelled to clear the court and address Costello’s questionable witness box antics. “Trump might have actually shot himself in the foot if, for whatever reas…