Pennsylvania Attorney General Kathleen G. Kane was "on a mission, a mission of revenge," when she orchestrated a "cloak-and-dagger" operation to illegally leak information to vilify a critic, prosecutors said Tuesday in the opening of Kane's trial on perjury and obstruction charges.

To the contrary, Kane was a victim grappling with lies from her former second-in-command and a political consultant who have repeatedly covered up their own roles in the leak, her defense argued before the jury in Montgomery County Court in Norristown.

Kane, 50, was charged last year after prosecutors said she had illegally leaked secret grand jury information to embarrass former state prosecutor Frank Fina, and later lied under oath to cover it up.

"Revenge is best served cold," prosecutor Michelle Henry in opening arguments, citing a line she attributed to Kane.

"At its core, this case is very simple," Henry told the jury of six men and six women. "The defendant wanted to get revenge against someone."

Kane left a trail documenting her lies and lawbreaking, Henry said, including text messages, emails, and phone records that will be presented at trial.

While the defense has portrayed Kane as a high-minded prosecutor who left the details of the leak to others, Henry described her as obsessed with Fina, once the office's most high-profile prosecutor as the overseer of corruption cases.

She said Kane blamed him for a 2014 article in the Inquirer that disclosed that Kane had secretly shut down a sting investigation without bringing charges against Philadelphia Democratic officials who were caught on tape pocketing cash from an undercover agent.

Figuring that Fina had leaked that story, Kane, Henry said, decided to give him a taste of the same, providing a different newspaper with secret grand jury information to suggest that he had mishandled a corruption case involving allegations that a Philadelphia civil rights leader had misused state money.

Henry said Kane pushed hard for the Daily News to publish that story, texting "Where's my article?" to political consultant Josh Morrow in 2014 when she grew impatient for publication.

Henry, the first assistant prosecutor in Bucks County, called in to assist the Montgomery County team, provided a complex account of the action of two key government witnesses - Morrow and Adrian King, Kane's first deputy attorney general.

The two men each helped get the confidential material to the Daily News, though King has said he had no idea that he was serving as a courier of such information.

Henry said they may minimize their own roles in the leak when they take the stand. In addition, she said, Morrow conspired with Kane at one point to pin the entire crime on King.

Morrow now appears to be fully aligned with the prosecution. It was revealed Tuesday that he has been given immunity from prosecution in return for his testimony.

But defense lawyer Gerald Shargel promised a bruising cross-examination of Morrow, King, and other former top aides to Kane. He accused prosecutors of whitewashing the aides' own "perjury." "They lied about their own involvement," he said.

While the prosecution said the case boiled down to an ugly feud between Kane and Fina, Shargel said Kane barely knew Fina and their overlapping time in office amounted to little more than a 10-minute meeting during her first week in office.

"The attorney general cared not one whit about Frank Fina," Shargel said.

Kane is also accused of lying to the grand jury. Henry ticked off a litany of Kane's alleged lies, including her statement that she had never signed a secrecy oath prohibiting her from disclosing the leaked information and that she had not read the newspaper article based on the leaked documents until months after it was published.

Shargel acknowledged some misstatements by Kane in his opening arguments Tuesday, calling them an "honest mistake."

For example, he said, the attorney general simply forgot that she signed a secrecy oath in her first week of office, saying it slipped her mind as one event among many in a tumultuous week. Prosecutors recovered the oath months after Kane testified that she had signed no such document.

Shargel also acknowledged that Kane "wanted to get the story out" regarding Fina and the probe of the civil rights leader. But he insisted that Kane did not select the grand jury material that made its way to the Daily News.

"Let me be clear: Attorney General Kathleen Kane did not leak any grand jury material," Shargel said. "It just does not make sense that she would risk her reputation and her career."

Under questioning from District Attorney Kevin R. Steele, Montgomery County Detective Paul Bradbury, the first witness in the trial, detailed key evidence gathered in the case, including emails, phone records, and documents from the grand jury that investigated the leak and referred the case to the District Attorney's Office.

"This is war," Kane wrote in one email, sent on the morning the Inquirer published its article on the aborted sting. Her media consultant, J.J. Balaban, advised her to "make war with Fina but not with the Inquirer."

Bruce Beemer, who served as Kane's first deputy from 2014 until last month, testified about his stunned reaction when he saw the Daily News article that was based on secret grand jury information.

"I was shocked," he said. "I couldn't believe it."

Beemer said he worried that the leak had come from the Attorney General's Office.

His testimony is to resume Wednesday morning. The trial, before Judge Wendy Demchick-Alloy, is scheduled to last one week.