Attorney General Eric Holder on Thursday pushed back against criticism for choosing to read terror suspect Faisal Shahzad his Miranda Rights within hours after his arrest, saying that the readings have not impeded this investigation or prior ones.

"As we've seen in prior investigations, the giving of Miranda warnings has not deterred people from talking to us and Mr. Shazad is continuing to cooperate with us," Holder told a Senate appropriations subcommittee hearing.

Holder cited a number of terror suspects who have continued to cooperate with federal authorities after being read their Miranda rights, including Daniel Boyd and his son Dylan, who were accused along with six others last year of leading a jihadist terror cell in North Carolina. 

Holder said Miranda warnings should not be seen as "conferring a right on somebody or treating them a special way. It is allowing us to make sure that statements they give to us are going to be admissible in court."

Sen. John McCain, R-Ariz., and other Republicans say Shahzad, a naturalized U.S. citizen, should have been treated as an enemy combatant out of the gate. Sen. Joe Lieberman, I-Conn, said as far as he's concerned, Shahzad lost his entitlement to Miranda Rights when he was arrested on terrorism charges.

Shahzad was not immediately Mirandized after authorities yanked him off a Dubai-bound flight from New York Monday night. John Pistole, deputy FBI director, said Tuesday that agents interviewed him under the "public safety exception" to determine whether there was an imminent threat. 

He was later read his rights and waived them, according to the White House.

At Thursday's hearing, Holder said the questioning of Shahzad by federal agents is "ongoing" and "there is simply no higher priority than disrupting potential attacks and bringing those who plot them to justice." Holder said Shahzad has provided "useful information."

Holder cited an earlier thwarted plot to bomb New York City's subway system, in which a key participant, Najibullah Zazi, pleaded guilty to terrorism violations.

The Shahzad and Zazi cases reflect "exemplary investigative efforts" by federal agents, law enforcement officers and Justice Department prosecutors, the attorney general said.