The Senate Homeland Security Committee will hold a public hearing over the prostitution scandal that involved Secret Service agents and members of the U.S. military in Colombia. The hearing is scheduled for May 23. Sen. Joe Lieberman, the committee’s chairman, said that both Secret Service Director Mark Sullivan and Acting Inspector General Charles Edwards will be called to testify. The committee has already sent Sullivan a list of questions, which he must answer by Monday. The scandal involved 20 alleged prostitutes and so far nine secret service members have been dismissed in connection with the scandal.