Reality TV hopefuls Michaele and Tareq Salahi said through their lawyer on Tuesday that the House Homeland Security Committee has drawn premature conclusions about the Nov. 24 incident, when they were able to get into the state dinner without being on an approved guest list.
The committee plans to vote Wednesday to subpoena the couple to testify.
In a letter Tuesday, the Salahis' lawyer, Stephen Best, gave examples of what he said were the committee's premature conclusions.
Best cited District of Columbia Delegate Eleanor Holmes Norton's characterization of the Salahis on Nov. 30 as "practiced con artists."
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Best also said that Chairman Bennie Thompson's chief oversight counsel told the Salahis' lawyers that if the couple did not testify at the Dec. 3 hearing, they would be viewed as modern-day versions of "Bonnie and Clyde."
"It is circumstances such as these for which the Fifth Amendment of the United States Constitution was designed to provide safe harbor," Best wrote.
The Secret Service is currently conducting a criminal investigation into the security breach; charges have yet to be referred for prosecution.
In identical declarations dated Dec. 7, the Salahis said:
"I am aware of statements made by certain members on the Committee on Homeland Security in which premature conclusions concerning my criminal liability have been made. ... The current circumstances warrant invocation of my Fifth Amendment privilege against self-incrimination."
The committee's top Republican, New York's Peter King, said he plans to ask Thompson to amend his subpoena to include White House social secretary Desiree Rogers. King had hoped Rogers would testify at the Dec. 3 hearing. She and the Salahis were no-shows.
The Secret Service and the White House social office together developed the security plan for the state dinner honoring the Indian Prime Minister Manmohan Singh. Thompson, D-Miss., is reluctant to subpoena Rogers - an Obama political appointee - because he maintains the Secret Service is responsible for security.
White House spokesman Robert Gibbs cited the separation of powers and a history of White House staff not testifying before Congress in explaining why Rogers, herself a guest at the dinner, wouldn't testify.
Three Secret Service officers have been put on administrative leave after the security breach. President Obama acknowledged that the system did not work as it should have, but he said the episode hasn't shaken his confidence in his protectors.
Secret Service Director Mark Sullivan has said that the security breach is his agency's fault but that the president was never at risk.