WASHINGTON—Former President Donald Trump on Thursday pled not guilty to plotting to overturn the 2020 election, as he vowed to fight the four charges in the third criminal indictment brought forth against him this year. Jack Smith, the Justice Department’s special counsel, alleges that Trump, in an effort to short-circuit the legitimate election results and remain in office, knowingly lied about the extent of voter fraud, orchestrated a plan to send slates of fake electors to Washington from states he had lost, and tried to disrupt the certification of the legitimate results on Jan.