HARRISBURG -- Two candidates for governor in 2010, Democrat Tom Knox and Republican Jim Gerlach, say Republican Tom Corbett should step down as attorney general if he plans to continue to lead an investigation into alleged corruption in the state Legislature.

"Tom Corbett should resign," Mr. Knox, a wealthy Philadelphia businessman, said yesterday after Mr. Corbett filed corruption charges against 10 people in the House Republican caucus.

"There is a perception that Corbett's actions as a prosecutor are calculated to benefit his campaign for governor," he said.

And there's another problem, he added.

"Unfortunately, Pennsylvanians will never know who was not charged or investigated, as the attorney general seeks to solidify GOP support in his campaign for governor" in the May 2010 primary.

Mr. Knox charged that Mr. Corbett "is choosing headlines over ethics."

Mr. Gerlach, a congressman from suburban Philadelphia who also is running in the GOP primary, has been saying similar things for the past several weeks.

He said that campaigning for governor while prosecuting corruption defendants in the legislature is "a clear and obvious conflict of interest" for Mr. Corbett.

"His failure to understand and acknowledge that conflict and immediately eliminate it is very disturbing," Mr. Gerlach said. "Pennsylvanians deserve to know whether Mr. Corbett is more interested in pursuing justice or advancing his political career."

He noted that the former attorney general of Virginia stepped down from his post before he ran for governor this year, a race he won on Nov. 3.

Before yesterday's charges were announced, Mr. Corbett had been taking heat from Democrats because he hadn't charged any Republicans in the corruption investigation.

Mr. Corbett said yesterday he doesn't see any conflict in being attorney general and running for the GOP nomination for governor next May.

"I am not running against any of these individuals" who were charged yesterday, he said. "We are following the evidence."

He said the investigation is being led by four "career prosecutors, who will do their jobs."

State Republican Chairman Rob Gleason praised Mr. Corbett for "conducting a thorough investigation," and added, "Ensuring that our tax dollars are spent properly and that our government is operating in an open and transparent fashion is not a partisan issue."

Gov. Ed Rendell, a Democrat, declined to comment on the charges brought against the House Republicans. But Chuck Ardo, a spokesman for the House Democratic Campaign Committee, had a lot to say. He attacked House Republicans for the "hypocrisy" that he claimed is shown by the charges brought by Mr. Corbett.

Mr. Ardo said that while Republicans often "rail against the dangers of government intrusion into people's lives," the grand jury report has evidence that House Republicans "improperly used a taxpayer-funded database to gather personal information on Pennsylvanians simply to improve Republican chances of winning elections."

Mr. Ardo said that the GOP, which "trumpets the evils of government, [used] $9 million ... to fund computer contracts researching intimate details of people's lives that could be used for political campaigns."

Rep. Sam Smith of Punxsutawney, who took over as the top House Republican in January 2007 after Speaker John Perzel lost his post, called the charges filed yesterday against Mr. Perzel and others "alarming and shocking," and, if proven in court, "would represent an unacceptable breach of the public's trust."

But Mr. Smith insisted that House Republicans understand the separation between using taxpayers dollars for proper constituent service and using campaign dollars for political purposes.

House Republicans "have understood there is a line between legislative work and campaign work," he said. House Republican procedures "generally speaking, have worked," he added, and "with continual monitoring and updating, we anticipate they will continue to work when adhered to."

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