Former Pennsylvania Attorney General Kathleen G. Kane's fight to reverse her perjury conviction reached Superior Court on Wednesday, another milestone in a long march that so far has kept Kane from serving a county jail sentence.

Her appeals lawyer, Joshua D. Lock,  appeared before a three-judge panel to ask it to undo Kane's August 2016 conviction for illegally leaking grand jury information to embarrass a political foe and then lying to investigators about it. Lock focused on one argument — that the special prosecutor who investigated Kane had been granted too much power.

Kane, 51, a Scranton-area resident, did not attend Wednesday's court session in Philadelphia.  Facing 10 to 23 months in the Montgomery County Correctional Facility, Kane remains free while she pursues her appeal in the state courts.

Kane was the first woman and first Democrat elected the state's top prosecutor. The path to her conviction was a convoluted one that began when the Inquirer disclosed in 2014 that Kane had secretly ended a bribery investigation involving state legislators from Philadelphia.

To retaliate against a former state prosecutor whom she blamed for the story,  Kane leaked secret grand jury information that she thought would embarrass him.

It backfired. The judge who presided over the grand jury appointed a special prosecutor, Thomas Carluccio, to investigate the leak. After subpoenaing 30 witnesses, Carluccio pinned it on Kane and accused her of lying about her actions. Building on Carluccio's inquiry, prosecutors in Montgomery County, where the grand jury had been based, brought the criminal case against Kane.

Kane challenged the legality of Carluccio's appointment before her trial in an appeal to the state Supreme Court. The high court rebuffed her, 4-1.

Lock argued Wednesday that another issue remained unresolved: whether Carluccio had been improperly granted the ability to use subpoenas to force witnesses to testify. Lock asked the panel to toss out Kane's conviction on the ground that Carluccio's use of subpoenas fatally tainted his investigation.

Prosecutors argued that stripping special prosecutors of subpoena power would neuter them. In court Wednesday, Montgomery County  Deputy District Attorney Robert M.  Falin argued a different point: that county prosecutors on their own had turned up the key evidence against Kane apart from Carluccio's investigation. Among other breakthroughs, he said, was the discovery of incriminatory text messages between Kane and a political consultant involved in the grand jury leak.

The  Superior Court panel was made up of two Democrats, Anne E. Lazarus and Carolyn H. Nichols, and a Republican, Paula F. Ott. It made no ruling and is under no time constraint to rule.

If the panel were to rule against her, Kane could appeal to the state Supreme Court, which would not be required to take up the case.