The judge in former President Donald Trump’s $370 million civil lawsuit in New York—who, even before the trial began, ruled the former president liable for fraud—has sent a sharply worded email to President Trump’s attorneys defending his impartiality. Judge Arthur Engoron’s Feb. 8 email to Trump attorney Cliff Robert chides the lawyer for questioning the judge’s objectivity. “You and your co-counsel have been questioning my impartiality since the early days of this case, presumably because I sometimes rule against your clients,” Judge Engoron wrote. “That whole approach is getting old.” The insistence on his objectivity—and rebuke of Mr. Robert for...