The conventional wisdom has always said that a sitting president cannot be indicted. Under current law, a President is immune from civil lawsuits in federal court, when it comes to his official acts as president. This is because of Nixon v. Fitzgerald, a 1982 Supreme Court ruling. There, the Supreme Court wrote: “The ‘singular importance of the President’s duties’ warrants a stay where civil actions, such as this one, ‘frequently could distract a President from his public duties to the detriment of not only the President and his office but also the Nation that the President was designed to serve.’”
From this case it was always thought that an indictment would similarly be barred.
However, nothing in the Constitution or federal law explicitly says presidents are immune from indictment while they remain in office. So what’s the answer?
A legal memo unearthed by the New York Times and written for special prosecutor Kenneth Starr during the Clinton Administration concludes that the indictment of a President for acts done prior to taking office, is constitutional. Here is that memo (after the NYT letters):