Monica S. Lewinsky is preparing to testify next week at a pretrial hearing in the Linda R. Tripp wiretapping case that will determine whether their taped conversations can be used as evidence, according to her lawyers and friends of her family.

Prosecutors have "indicated they want her as a witness," said Lewinsky's lawyer, Plato Cacheris. "She's a very reluctant witness."

Tripp is charged with illegally taping a phone conversation with the former White House intern and illegally disclosing its contents to Newsweek magazine. Each charge carries up to five years in prison and a $10,000 fine upon conviction.

Lewinsky is one of several figures from the presidential impeachment case who could be called to testify at the hearing beginning Monday in Howard County Circuit Court. Judge Diane O. Leasure is being asked to rule on whether a central piece of evidence against Tripp, an audio tape of her chat with Lewinsky, can be used in court. Tripp also may take the stand, said her lawyers.

Lewinsky was on a witness list drawn up by State Prosecutor Stephen Montanarelli months ago. From the prosecution's standpoint, Lewinsky's testimony is important because she can confirm that she did not give Tripp permission to tape their phone conversation--as is required under Maryland law.

Lewinsky was in Los Angeles yesterday evening, with plans to fly to New York over the weekend; friends said prosecutors asked her to be ready to testify Thursday. "She's trying to develop a new life. Any interest in vengeance against Linda Tripp is far outweighed by wanting to move on with her own life," said a family friend.

Tripp's lawyers argue that Lewinsky should not be allowed to testify about the recordings. She knew of how and when the tape was made only because Tripp told independent counsel Kenneth W. Starr's office, under a grant of immunity, which in turn told Lewinsky, Tripp's lawyers say. They argue that evidence that is directly or indirectly the product of immunity is considered tainted and cannot be used in court.

"I think the prosecutor will want to try to show that her testimony is not tainted," said Tripp lawyer David Irwin. "But her testimony relies partially on what she learned from the office of the independent counsel."

Irwin said calling Tripp to testify is contingent "on what the prosecution does."

The crux of the state prosecutor's argument for using the tape in court lies in the chronology of how immunity was granted in early 1998. On Jan. 16, Starr's office gave Tripp a letter promising immunity; she handed over the tapes that day. On Feb. 19, a federal judge approved the immunity deal. Montanarelli argues that the tape is his to use because her immunity didn't kick in until the judge signed off on it.

Yesterday, Montanarelli filed a motion asking that the second phase of next week's proceedings be closed to the media and public because it will deal extensively with grand jury evidence.

"Grand jury testimony is secret until a trial. So we believe that is reason to close the hearing," he said.

After the hearings, Tripp's trial is scheduled for Jan. 18.

The Associated Press contributed to this report.