Attorney General Eric Holder Jr. defended himself Thursday amid growing criticism and calls for his resignation, saying on Capitol Hill that he has done a "good job" and would remain the nation’s top law enforcement officer until he has accomplished his goals.

Holder appeared before the Senate Appropriations Committee following weeks in the hot seat over the Justice Department’s handling of leak investigations that involved seizing evidence from news reporters.

The committee’s ranking member, Senator Richard Shelby (R-Ala.), told Holder that recent controversies have "overwhelmed the Justice Department and cast a shadow of doubt upon the attorney general." The attorney general replied: "I have not done a perfect job. I have done a good job. But I’m always trying to do better."

As if Holder needed any more headaches, his scheduled appearance came one day after publication of a leaked, top-secret court order that gave the National Security Agency the power to review millions of phone call records for Verizon customers. The Guardian newspaper first published the court order, which the Foreign Intelligence Surveillance Court issued in April.

Civil liberties groups assailed what they called dragnet-style surveillance of Americans who are not suspected of criminal wrongdoing. White House officials were on the defensive, telling reporters that the authority to review the records, via a section of the Patriot Act, has received congressional blessing and court approval.

The revelation of the court order could compel the Justice Department to open another high-profile leak investigation, a move that could add fuel to concerns among journalists and lawmakers that prosecutors too zealously—and perhaps inappropriately—have pursued information from the press during criminal probes.

Holder stressed in his testimony Thursday that Justice Department leak investigations are carried out to identify and prosecute government officials who disclose secrets, "not to target members of the press or discourage them from carrying out their vital work."

The department, Holder said, has not prosecuted "and, as long as I’m Attorney General, will not prosecute any reporter for doing his or her job."

‘Fully briefed’

Members of Congress immediately began calling for confidential briefings about government surveillance—meetings that would include Holder.

Holder assured committee members that the Justice Department has "fully briefed" Congress on the government’s collection of phone records under Section 215 of the Patriot Act.

Congress has repeatedly reauthorized the provision, which allows the government to apply to the foreign intelligence court for orders compelling the production of "tangible things"—for instance, phone records—during terrorism investigations.

The top-secret order disclosed this week did not authorize the interception of the content of any call. The order, signed by U.S. District Judge Roger Vinson, gave the government authority to review three months’ of Verizon calls both domestic and international. The data would also show where a call was made and how long it lasted.

Senator Mark Kirk (R-Ill.) asked Holder whether the 120 million phone records intelligence officials obtained involved members of Congress or U.S. Supreme Court justices.

"I don’t think this is an appropriate setting for me to discuss that issue," Holder responded. His answer didn’t satisfy Kirk. "I would interrupt you and say, the correct answer would be to say, ‘No, we stayed within our lane and ensure we did not spy on members of Congress,’" he said.

Senators made it clear that the National Security Agency surveillance program is legal and has existed for seven years, stretching back past Holder’s tenure to the George W. Bush administration.

The top-ranking members of the Senate Intelligence Committee, senators Dianne Feinstein (D-Calif.) and Saxby Chambliss (R-Ala.), defended the phone record program as necessary to protect the United States.

"This is nothing new," Chambliss said. "It has proved meritorious because we have gathered significant information on bad guys, but only on bad guys, over the years."

Senator Dick Durbin (D-Ill.) said the flare-up over the use of the Patriot Act to seize U.S. citizens’ phone records could lead to a re-evaluation of the law. "Theoretically, we could step right up and change the law," Durbin said. "It’s not going to happen."

‘Come clean’

Civil liberties groups demanded explanations from the government regarding the scope and context of the top-secret court order. Jameel Jaffer, the American Civil Liberties Union’s deputy legal director, called the surveillance program revealed in the court order "beyond Orwellian."

Michelle Richardson, the organization’s legislative counsel, urged the federal government to end the tracking program and said Congress should launch an investigation.

"Since 9/11, the government has increasingly classified and concealed not just facts, but the law itself," she said. "Such extreme secrecy is inconsistent with our democratic values of open government and accountability."

The civil liberties group Electronic Frontier Foundation called on the federal government to "come clean" about the extent of its surveillance programs. In an unrelated case, the group is fighting in Washington federal district court to obtain a copy of a lengthy opinion in which the Foreign Intelligence Surveillance Court concluded the government had run afoul of Fourth Amendment protections.

The foreign surveillance court was created under the federal Foreign Intelligence Surveillance Act of 1978 and comprises sitting federal district judges. The National Security Agency’s general counsel’s office drafts warrant applications at the request of federal intelligence agencies. Judge Reggie Walton of the U.S. District Court for the District of Columbia presides.

The judge who signed the Verizon order, Judge Roger Vinson of the U.S. District Court for the Northern District of Florida, served on the surveillance court from May 2006 until May of this year. Vinson previously made national headlines in January 2011, when he struck down the federal health care reform law as unconstitutional and famously compared the law’s provision requiring individuals to buy health insurance to a hypothetical government mandate that everyone eat broccoli.

According to a letter submitted to Congress by the Justice Department in April, the surveillance court approved 1,788 applications filed by the government in 2012 for electronic surveillance; the government withdrew one additional application. The court did not deny any of the government’s requests.

Randal Milch, executive vice president for public policy and general counsel of Verizon, and William Petersen, vice president, general counsel and secretary of Verizon Wireless, did not return requests for comment.

Milch, however, sent a letter to Verizon employees addressing the recent reports that was posted Thursday on the company’s website. In the letter, Milch said he had no comment on the reports, but that if Verizon ever did receive an order such as the one reported on, the company "would be required to comply."

"Verizon continually takes steps to safeguard its customers’ privacy. Nevertheless, the law authorizes the federal courts to order a company to provide information in certain circumstances," Milch wrote.

A White House spokesman, Josh Earnest, told reporters that "there is a robust legal regime in place governing all activities conducted pursuant to the Federal Intelligence Surveillance Act."

"The president," Earnest said, "welcomes a discussion of the tradeoffs between security and civil liberties."

Digging in

Holder is unlikely to escape criticism about leak investigations—at least not for several more weeks. Republicans on the House Judiciary Committee on Thursday asked the attorney general to come back and explain remarks he gave in May—when he said he had not been involved in the potential prosecution of any journalist in a leak probe.

As the pressure mounts, Holder is digging in. On Wednesday, Holder told NBC News that he has no intention of resigning. He has said several times publicly that he doesn’t want to remain in office for the entirety of Obama’s second term.

During the Senate hearing Thursday, Shelby asked Holder where the tipping point was for his departure from the Justice Department.

"The tipping point might be fatigue," Holder said. "You get to a point where you just get tired."

Holder added: "There are certain goals I set for myself and for this department when I started back in 2009. When I get to a point I think I’ve accomplished all the goals I set, I’ll sit down with the president and talk about a transition to a new attorney general."

 Todd Ruger and Zoe Tillman are reporters for The National Law Journal, a Legal affiliate based in New York.