Marquez wrote a letter to House Speaker John A. Boehner, read aloud on the House floor last Thursday, informing him she had received the subpoena. The disclosure process is required under House rules.
Marquez's letter did not specify the nature of the inquiry, nor did it say whether she had any other contact with federal investigators. Since then, she has not responded to requests for comment from The Times. Cardenas declined to grant an interview and his spokesman, Paul Kincaid, would not make the congressman available.
Kincaid said Marquez followed House rules by reporting the existence of the subpoena. "Other than that, there isn't anything I've found out," he said.
News of the subpoena was broken this week by Roll Call, a publication that covers
Cardenas hired Marquez in 2011, when he was a member of the
Marquez is now director of that office and earned more than $62,000 last year, federal records show.
Cardenas has backed an array of politicians in the San Fernando Valley, including L.A. City Council members Felipe Fuentes and Nury Martinez and former State Assemblyman Raul Bocanegra. Those politicians routinely support each other, providing endorsements and other campaign resources.
Last fall, Marquez signed in as one of many observers at the Los Angeles County Registrar-Recorder/County Clerk's office to monitor ballot counting for the tight state Assembly race between Bocanegra and community volunteer Patty Lopez. Three of those days were weekdays, according to county records. Lopez eventually won.
Kincaid declined to say whether Marquez had taken any leave to work on campaign issues, citing an internal policy that prohibits disclosure of personnel matters. He also would not say what, if anything, Cardenas has been told about the investigation.
Many congressional aides serve dual roles, as both political and campaign staffers. At times, they use vacation days or unpaid leave, especially to work on close elections.
Campaign records show Cardenas' campaign committee paid Marquez $5,775 in 2013 and 2014, including $475 for phone expenses. Other payments were for administrative or political services, according to records.