WASHINGTON (CNN) -- Congressional Democrats sharply criticized the Bush administration Friday for deliberately trying to silence critics of its Iraq policy, after senior White House aide I. Lewis "Scooter" Libby was indicted for his alleged role in revealing the identity of CIA agent Valerie Plame.Plame's husband, diplomat Joseph Wilson, was an outspoken critic of the Bush administration's decision to invade Iraq. (Related story)"The criminal indictments of a top White House official mark a sad day for America and another chapter in the Republicans' culture of corruption," House Minority Leader Nancy Pelosi, D-California, said. "At the heart of these indictments was the effort by the Bush administration to discredit critics of its Iraq policy with reckless disregard for national security and the public trust," Pelosi said.Senate Minority Leader Harry Reid, D-Nevada, called on President Bush to address the "very serious questions raised by the (Plame) investigation," and sought to broaden the Democratic criticism by charging the White House willfully used faulty intelligence data to justify its case for war against Iraq."This case is bigger than the leak of highly classified information," Reid said. "It is about how the Bush White House manufactured and manipulated intelligence in order to bolster its case for the war in Iraq and to discredit anyone who dared to challenge the president."But Sen. Kay Bailey Hutchison, R-Texas, cautioned that people should not rush to judgment about whether Libby is guilty of breaking any laws."Out of respect for our system of justice, everyone needs to take a deep breath and not judge those involved until it has been proven they are anything other than innocent," Hutchison said. "Today's announcement is the middle of the process, not the end."Libby was indicted on counts of making false statements, obstruction of justice and perjury in the CIA leak probe. He has resigned his position as Cheney's top aide.