HARRISBURG - Pushing for more evidence even after charging Pennsylvania Attorney General Kathleen Kane, Montgomery County investigators Thursday conducted a new search to test her testimony that she never signed a key oath of secrecy, The Inquirer has learned.

Montgomery County detectives executed the search warrant shortly after 11 a.m. at Kane's offices here, seeking an oath of secrecy she may have signed shortly after taking office pledging to keep years of grand jury investigations confidential.

In seeking such an oath, prosecutors who charged Kane last month with leaking confidential grand jury information are looking both to undermine a key element of her defense and raise new questions about her veracity.

Kane's criminal-defense lawyer, Gerald Shargel, declined to comment Thursday.

Kane spokesman Chuck Ardo said he did not have information about any secrecy oaths Kane has signed since taking office, or what time frame they might have covered.

"I can't confirm that is what the search warrant was after, or that there is such a document," Ardo said of Kane's secrecy oath.

Ardo did say the office was "cooperating fully."

The continuing investigation of Kane is being led by Montgomery County District Attorney Risa Vetri Ferman and her first assistant, Kevin Steele.

Their new line of inquiry is significant because Kane, facing criminal charges for leaking documents about a 2009 grand jury case, has maintained she cannot be held liable for the leak in part because she had never been sworn to secrecy in that matter.

Kane testified under oath last year that she was a stay-at-home mother at the time, and was not involved in any capacity with the 2009 grand jury.

She said that after she was sworn into office in January 2013, she signed oaths only for grand juries that were actively hearing cases.

"We don't go back and sign [oaths for] every grand jury from the beginning of time," she testified Nov. 17 before a new grand jury investigating her. "You can't do that."

Grand Jury No. 29

But Montgomery County investigators who executed the search warrant Thursday were reportedly seeking a simple notarized form, signed early in Kane's tenure, in which she swore to keep secret information from Grand Jury No. 1 - impaneled 35 years ago - through Grand Jury No. 32, according to people familiar with the matter.

The numbering dates to about 1980, when the state modernized its grand jury statute while making the attorney general's position an elective office.

The materials Kane is charged with leaking are associated with Grand Jury No. 29.

Kane's secrecy oath could prove critical to prosecutors, who charged her last month with conspiracy, perjury, obstruction, and other crimes for allegedly leaking grand jury information, lying about it under oath, and then spying on the investigation into her office.

Prosecutors allege Kane secretly released information to the Philadelphia Daily News about the 2009 investigation into the finances of Philadelphia civil rights leader J. Whyatt Mondesire. The newspaper story said Kane was questioning why the inquiry did not result in charges against Mondesire, and suggested that the matter had been bungled.

The case was handled by Frank Fina, a former top prosecutor in the Attorney General's Office with whom Kane was feuding.

Kane, 49, the first woman and Democrat elected to the office, has pleaded not guilty and is fighting the charges.

Smear alleged

Both she and her defense attorneys have painted the criminal case as an attempt by angry Republican men to smear her reputation.

For weeks late last year, Lanny J. Davis, her spokesman at the time, said Kane could not be charged with violating secrecy laws because she had not signed a secrecy oath related to the 2009 grand jury.

In a legal filing to the Supreme Court last November, Kane made the same argument.

The argument has been rejected by many in the legal community, including top lawyers on her own staff.

More recently, Kane's lawyers seemed to have distanced themselves from the argument. They did not dwell on the oath issues in a recent filing challenging a move by a disciplinary panel to suspend her law license.

In testimony to the grand jury investigating Kane, her then-chief of appeals, James Barker, said last year that she had "an implied ongoing obligation to honor grand jury information as secret, and such obligation does not expire even when a grand jury no longer is in session," according to court documents.

He further testified that any other interpretation "would completely undermine the secrecy requirements of the [state Grand Jury Secrecy] Act."

Kane fired Barker last spring, saying his dismissal was part of a restructuring of the office.

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