Ruth Bader Ginsburg isn’t the only judge Donald Trump has recently tangled with. The Republican presidential candidate is a prolific litigator. According to a USA Today investigation, Donald Trump and his companies have been involved in more than 4,000 lawsuits since 1970. Since Trump began his presidential campaign a year ago, he has become involved in 70 new lawsuits. One of the current cases alleges that Trump University has defrauded its students.