Washington (CNN) -- In what one member of Congress called "a charade," a couple that showed up at President Obama's first state dinner -- uninvited, the White House claims -- declined to answer questions surrounding the event before a House committee Wednesday.

Under questioning from House Homeland Security Committee Chairman Rep. Bennie Thompson, D-Mississippi, and others, Tareq Salahi repeated over and over again, "On the advice of counsel, I respectfully assert my right to remain silent and decline to answer your question."

The Salahis' attorney notified the committee in December that because of a pending investigation by federal prosecutors, they would not answer questions about how they gained entry to the White House on November 24, despite not being on the guest list to attend that night's state dinner for the prime minister of India.

In a brief statement that opened the often-contentious hearing, Salahi chastised the committee for requiring the couple to appear despite having been told the two would invoke their Fifth Amendment right against self-incrimination if subpoenaed. That, he alleged, is against the ethical rules of the Washington bar.

He incensed some committee members by reiterating the couple's respect for U.S. troops, the Secret Service and the president.

"You have shown effrontery here," said Daniel Lungren, R-California. He called it "an abomination" that the Salahis would invoke the name of those in uniform "and suggest that somehow what you do provides support to them."

"The Constitution protects fools," Lungren said. "The Constitution protects stupidity. The Constitution protects errant thought. Thank God it does."

"This was not a hearing looking for information," the couple's attorney, Stephen Best, told reporters after the hearing. "This was an opportunity for a public flogging."

"I think today's procedure is a charade," Rep. Mark Souder, R-Indiana, said in the hearing, referring to the Salahis' refusal to answer questions.

Other committee members also lambasted the couple, alleging they put their own desire for celebrity before the security of the president and are wasting the committee's time and taxpayers' money.

"I don't respect your right to take the Fifth Amendment. Not at all," Rep. Bill Pascrell Jr., D-New Jersey, told the couple.

"Were you there?" he asked Salahi, referring to the dinner.

When Salahi began, "On the advice ..." Pascrell interrupted him, asking, "Are you here right now? You gonna get an answer from your attorney on that?"

Pascrell noted the committee had offered to allow the couple to speak behind closed doors. After conferring with his attorney, Salahi said, "Yes, but you didn't offer us any legal protection."

Salahi's wife, Michaele, also invoked her Fifth Amendment right under questioning by committee members, but replied, "yes," when asked if she would return to testify after the investigation has concluded.

Asked by Thompson whether the state dinner appearance was part of a "reality TV stunt," Tareq Salahi said the couple was under a non-disclosure agreement and "should not discuss matters related to the television matter."

The Salahis contend they were told they could attend the program to honor India's prime minister, but the White House says they were not invited and were not on the guest list for the exclusive affair.

Best said after the hearing the couple received "representations that they relied upon" that they were invited guests. Two Secret Service investigators were privy to this information from a person who knows the Salahis, he said. "This was not a stunt, and they committed no criminal act."

There was no connection to any reality TV show, he said, and the Salahis were not seeking publicity. The couple has turned down multiple offers from the media to be "rewarded handsomely," he added.

"Whatever the real story is, it's on the other side of the gates of the White House, not with the Salahis," Best said. "They thought they were invited. ... If it was a misunderstanding, it was a misunderstanding caused by representatives of the government."

Tareq Salahi also noted in his opening statement that the couple's attorneys have offered to provide information to the committee, but that offer was declined by Thompson's staff.

"Those offers are not satisfactory," Thompson said. "These lawyers were not at the state dinner and have no firsthand knowledge of the facts."

Tareq Salahi also said the couple has provided phone records, e-mails and other documentary evidence to the committee.

There also was criticism of the White House in Wednesday's hearing.

Rep. Peter King, R-New York, said the White House "continues to stonewall" and will not allow social secretary Desiree Rogers to testify on the security breach.

Obama press secretary Robert Gibbs has said that allowing a White House staff member to testify before a congressional committee would violate the Constitution's separation of powers.

"I don't know what the White House is trying to hide," King said. "Obviously, something went wrong, and it originated with the White House, not the Secret Service."

Secret Service Director Mark Sullivan, in previous testimony before the committee, took responsibility for the security breach, acknowledging that "appropriate procedures were not followed."

Rep. Charles Dent, R-Pennsylvania, said Wednesday he thought it was "unfortunate" that Sullivan "had to take all that grief from us."

"I hold you responsible for it," he told the Salahis.

"Your actions ... made a mockery of this country, a mockery of our security," Rep. Sheila Jackson-Lee, D-Texas, told the couple. "I'm saddened, and I'm disappointed, and I'm outraged."

Best reiterated afterward the Salahis do not want the events surrounding the dinner to detract from the "extraordinary institution" of the Secret Service.

"They are Americans," he said. "They are proud Americans."