WASHINGTON (Reuters) - A former aide to U.S. Attorney General Alberto Gonzales told Congress on Wednesday she “crossed the line” by letting politics influence the Justice Department’s hiring process.

But Monica Goodling, the 33-year-old counsel to Gonzales who resigned after Congress began an investigation of the firings of federal prosecutors, said she had a limited role with the case that has triggered bipartisan calls for Gonzales to resign.

“I did not hold the keys to the kingdom,” said the former employee of the Republican National Committee who testified only after being granted immunity from prosecution.

“I was not the primary White House contact for purposes of the development or approval of the U.S. attorney replacement plan,” which originated at the White House shortly after President George W. Bush was re-elected in November 2004.

Indeed, Goodling, a graduate of conservative Christian leader Pat Robertson’s Regent University law school who served as a senior counsel to Gonzales and the department’s White House liaison, said Bush political adviser Karl Rove never contacted her about the firing of any prosecutor. One of the dismissed U.S. attorneys was replaced by a former Rove aide.

Goodling was subpoenaed as part of the House of Representatives Judiciary Committee’s probe of Gonzales’ firing last year of nine of the 93 U.S. attorneys, all Bush appointees.

She also faces an internal Justice Department investigation into whether she brought political questions into the hiring process for career positions, such as assistant U.S. attorneys. That would violate federal law.

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REGRETS MISTAKES

“I do acknowledge that I may have gone too far in asking political questions of applicants for career positions and may have taken inappropriate political considerations into account on some occasions,” Goodling told the House panel.

“I regret these mistakes,” said Goodling.

Asked if she believed she had done anything illegal, Goodling said: “I know I crossed the line.”

“But I didn’t mean to,” she added.

Bush and Gonzales have said the firings of U.S. attorneys were justified though mishandled. They have rejected charges that some were politically motivated to impact ongoing federal probes involving Democratic or Republican lawmakers.

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Gonzales, in earlier testimony before the committee, said he had not gone back to talk to staff involved in the firings “in order to protect the integrity” of the investigations.

Yet Goodling said Gonzales told her about his recollections of the dismissals in March, shortly before she resigned. “I didn’t know that it was maybe appropriate for us to talk about that at that point, and so I just didn’t,” she said.

Goodling placed some of the blame for the furor over the fired prosecutors on Deputy Attorney General Paul McNulty, denying claims she had withheld information from him before he testified to Congress in February.

“Despite my and others’ best effort, the deputy’s public testimony was incomplete or inaccurate,” Goodling said, adding, “I believe the deputy was not fully candid about his knowledge of White House involvement in the replacement decision.”

In a statement, McNulty said he testified truthfully “based on what I knew at that time.”

“Ms. Goodling’s characterization of my testimony is wrong and not supported by the extensive record,” said McNulty, who recently announced plans to resign.

Committee Chairman John Conyers, a Michigan Democrat, vowed to push ahead with the probe, saying: “The issues we are examining -- which include possible obstruction of justice, misleading Congress ... are quite serious.”

But Rep. James Sensenbrenner, a Wisconsin Republican, called it a “fishing expedition. There ain’t no fish in the water.”