A more stringent regulation, which would have banned romance between all professors and undergraduates, was voted down.
The list of schools with these policies in place has grown to include Stanford, Harvard, Yale, The College of William and Mary, the University of Connecticut and Northwestern University.
Laura Kipnis, a professor in Northwestern's School of Communication, criticized her school's policy in a controversial essay in the Chronicle of Higher Education, arguing that the ban assumes that professors are predators, and also that these policies infantilize students.
This policy applies to all officers of instruction, research and the libraries, including student officers of instruction and research and graduate and undergraduate teaching assistants.
You may read and download the policy in its entirety here: No staff member at Columbia should participate in supervision, employment actions, evaluation, advising or mentoring any Columbia University student with whom that staff member has or has had a consensual romantic or sexual relationship, except in unusual circumstances.
Several psychologists who teach at local schools also stress the difficulty of regulating human behavior, regardless of what's printed in a college policy handbook.