WASHINGTON (Reuters) - Karl Rove, who had been one of President George W. Bush’s top aides, was subpoenaed on Thursday for a second time to testify in a congressional probe of the administration’s firing of federal prosecutors.

Karl Rove is pictured at the end of a roundtable meeting on financial literacy chaired by U.S. President George W. Bush (not pictured) in the Roosevelt Room of the White House in Washington April 25, 2007. Rove, who had been one of President George W. Bush's top aides, was subpoenaed on Thursday to testify before a congressional panel investigating the administration's firing of nine federal prosecutors. REUTERS/Jason Reed

The former deputy White House chief of staff quickly indicated through his attorney he would again refuse, citing executive privilege that protects conversations between a president and his staff.

House of Representatives Judiciary Committee Chairman John Conyers issued the subpoena for Rove to testify on July 10 after months of failed efforts to get him to voluntarily answer questions under oath about the 2006 firing of nine of 93 U.S. attorneys. Critics charge the dismissals were politically motivated. Rove and the White House have denied any wrongdoing.

In December, the Senate Judiciary Committee voted to hold Rove and White House Chief of Staff Josh Bolten in contempt for failing to comply with its subpoenas in the same probe.

“While the (House) committee has the authority to issue a subpoena, it is hard to see what this will accomplish, apart from a ... replay of the same issues that are already the subject of litigation,” Rove’s attorney, Robert Luskin, wrote Conyers, a Michigan Democrat.

A court fight over the subpoenas may not be settled until after Bush’s term ends in January.

Democrats have charged the firings may have been in retaliation for prosecutors being too soft on Democratic lawmakers or too tough on Republican ones. The controversy ignited a firestorm that led to the resignation of Attorney General Alberto Gonzales.

Rove stepped down as deputy White House chief of staff last year. He had also served as Bush’s political strategist and is now a political commentator.

Conyers said: “It is unfortunate that Mr. Rove has failed to cooperate with our requests. Although he does not seem the least bit hesitant to discuss these very issues weekly on cable television and in the print news media, Mr. Rove and his attorney have apparently concluded that a public hearing room would not be appropriate.”

‘POLITICAL THEATER’

White House spokesman Tony Fratto noted the House committee had rejected Rove’s offers to answer questions privately or in writing. “They want their political theater,” Fratto said.

The House and Senate Judiciary committees have been investigating the ouster of the prosecutors for more than a year.

The Justice Department’s Office of Professional Responsibility is conducting its own probe into what Conyers describes as political prosecutions of Democratic lawmakers, including former Alabama Gov. Don Siegelman.

A federal court this year released Siegelman from prison, pending appeal. He had begun serving a more than seven-year sentence in 2007 after being convicted of corruption.

Critics charge Siegelman and other Democrats were victims of a smear campaign by Rove. He has denied it.

(Additional reporting by Jim Vicini and Tabassum Zakaria)