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A former California county clerk plans to plead guilty to fabricating recent death threats against herself — but her lawyer says she still stands by allegations made two decades ago that sent a man to prison for 19 years.

A plea hearing for Karen Mathews Davis, the longtime clerk-recorder for Stanislaus County, is scheduled for June 1 in federal court.

One person who will be closely following the proceedings is Roger Steiner, who was convicted in 1997 of viciously attacking Davis as part of a bizarre tax protest.

Karen Mathews Davis talks to KCRA 3 in Feb. 2014. KCRA

When Davis was arrested in 2015 for sending threatening letters to herself and lying about it to federal agents, prosecutors decided to take another look at the Steiner case.

Now Steiner, who has congestive heart failure and has been in and out of the hospital, hopes Davis will clear his name before he dies.

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"I want her to tell the truth about what happened 20 years ago," Steiner, 79, told NBC News on Friday.

"I don't have long to live," he said. "I hope I stay alive long enough so I can see the end of this."

A spokeswoman for federal prosecutors in Sacramento said "it's within the realm of possibility" that the Steiner case could come up during the plea hearing.

Davis' lawyer, however, told NBC News that he doesn't expect that to happen.

"I think she testified to the truth back then. That's what she's told me," said the attorney, Randy Thomas.

Steiner always maintained his innocence, even after a jury found him guilty of beating Davis, supposedly to punish her for refusing to remove tax liens against a group that didn't recognize the authority of the federal government.

Soon after Steiner was released in 2013, Davis was arrested on charges of lying to the feds — not about the 1990s attack, but about threatening letters she claimed to have received in recent months.

One note suggested she would be shot in the head if she didn't drop an ill-fated bid for Congress, according to court documents. Another included the phrase "white bitch" — an epithet that she said had been used in the earlier assault.

Roger Steiner sits outside his motor home in Fresno, Calif., Oct. 30, 2015. John Westberg / Modesto Bee via ZUMA Wire

She suggested Steiner might be a suspect, but federal investigators quickly ruled him out, according to court filings. They gave Davis a polygraph, which she flunked before admitting she wrote both notes to herself, court documents said.

Her admission drew scrutiny to the old allegations against Steiner, and the U.S. Attorney's office said it was taking a new look at her claims and his conviction. That probe, according to a spokeswoman for the prosecutor's office, is ongoing.

Steiner's attorney, Patrick Fortune, said that even if his client were exonerated, it wouldn't give him back the years he spent behind bars.

"But I hope we get some vindication for Roger out of all of this," Fortune said.