Washington ( CNN ) -- David Nieland , who helped draw attention to what he said were shortcomings in the government 's probe of a Secret Service prostitution scandal , resigned from his job at the Department of Homeland Security inspector general on Aug. 9 , months after he was caught up police prostitution sting . Deputies in Broward county , Florida , conducting an anti-prostitution operation on May 2 stopped Nieland after he was seen entering and leaving a location they were monitoring for prostitution activity , according to U.S. government sources . Nieland was an investigator with the DHS inspector general , who claimed that political interference appeared to cause the inspector general to hold back findings in an investigation of Secret Service agents involved with prostitutes in Cartagena , Colombia . The Office of Inspector General confirmed that Nieland `` separated '' from federal service in August , but added `` As a matter of policy , the OIG does not comment on investigative or personnel matters . '' U.S. government sources said Nieland , wearing casual clothing including khakis , told deputies who stopped him he was there as a law enforcement officer working on an anti-human trafficking operation . His story prompted the deputies to stop their operation , for fear of conflicting with a federal probe , according to those U.S. government sources . Nieland told his bosses that he had been stopped because of a broken taillight , but his superiors found out from local authorities that he was caught in the local prostitution operation . CNN attempted to reach Nieland in recent weeks without success . He told the New York Times the story was n't true . Secret Service Director Julia Pierson resigns .
Nieland was an investigator with the DHS inspector general . He raised concerns over Broward County Sheriffs Deputies trying to investigate the OIG involvement with prostitutes . David Nieland was spotted by OIG who were conducting an anti-prostitution operation .