FILE - In this April 25, 2012 file photo, Homeland Security Secretary Janet Napolitano testifies on Capitol Hill in Washington. Expanding the prostitution investigation, the Secret Service acknowledges it is checking whether its employees consorted with strippers and prostitutes in advance of President Barack Obama's visit last year to El Salvador. The disclosure comes not long after the Homeland Security secretary assured skeptical senators that the prostitution scandal in Colombia appeared to be an isolated incident. (AP Photo/Susan Walsh, File)

Photo by: Susan Walsh

FILE - In this April 25, 2012 file photo, Homeland Security Secretary Janet Napolitano testifies on Capitol Hill in Washington. Expanding the prostitution investigation, the Secret Service acknowledges it is checking whether its employees consorted with strippers and prostitutes in advance of President Barack Obama's visit last year to El Salvador. The disclosure comes not long after the Homeland Security secretary assured skeptical senators that the prostitution scandal in Colombia appeared to be an isolated incident. (AP Photo/Susan Walsh, File)