Former housing secretary Henry G. Cisneros suffered a courtroom setback yesterday when a federal judge ruled that a jury will be able to hear tape recordings of his telephone conversations with a former mistress. An independent counsel plans to use the tapes at Cisneros's September trial on charges that he lied to the FBI about $250,000 he gave to the woman, Linda Medlar Jones.

During a three-week hearing before U.S. District Judge Stanley Sporkin, Cisneros's attorneys vehemently argued against admitting the tapes, questioning their authenticity. Jones, who said she recorded conversations with Cisneros for nearly four years without his knowledge, admitted that she had edited several tapes to remove exchanges in which it could have appeared that she was blackmailing him.

The question of the tapes' admissibility was sensitive enough that they were not played publicly during the hearing. Sporkin privately listened to excerpts and reviewed transcripts of the recordings, in which Cisneros and Jones wrangle with their emotions as well as the financial arrangements.

Jones, who said she made 88 tapes between 1990 and 1993, destroyed the originals but kept copies. Independent counsel David M. Barrett had hoped to use 26 of the copies, four of which had been edited by Jones. Sporkin ruled that the 22 unaltered tapes can be admitted at trial in full, along with unedited passages from the other four tapes.

Associate independent counsel James P. Fleissner contended that the recordings show Cisneros conspired with Jones to lie to investigators vetting him for confirmation as the Clinton administration's first housing secretary in January 1993. In the tapes, Cisneros and Jones discuss what they will tell the FBI and presidential transition team about his payments to her, Fleissner said.

Cisneros and Jones began their affair in 1987, while he was mayor of San Antonio, and he made the relationship public the following year. But by 1991 they had broken up and he reconciled with his wife.

During federal confirmation proceedings, Cisneros told background investigators he provided Jones with some money as a humanitarian gesture, but never gave her more than $10,000 a year and the payments had already stopped. Barrett's lawyers maintain that he dramatically underestimated the payments and continued channeling money to Jones until January 1994.

Cisneros, who is now a television executive in Los Angeles, did not attend the hearing. He has pleaded not guilty to an 18-count indictment.

Jones is cooperating with Barrett's office in hopes of engineering an early release from a 3 1/2-year prison term. She pleaded guilty last year in a bank fraud case in Texas that was a spinoff of Barrett's investigation.

Although the ruling went against Cisneros, the recent hearing raised doubts about Jones's effectiveness as a witness, with even Sporkin questioning her credibility. During the hearing, she admitted that she had attempted to pass off the copies of tapes as originals in 11 previous meetings with investigators.

Defense attorney Brendan V. Sullivan Jr. contended that the accuracy of the copies cannot be trusted because Jones had lied about them so frequently. He also argued that the tapes were illegally made by Jones for blackmail purposes.

But in his 14-page ruling, Sporkin cited the testimony of a tape expert who said none of the tapes contained instances of splicing. He dismissed the notion of blackmail, saying he believed Jones when she asserted that she made the recordings as proof of promises Cisneros made to her.

"Most importantly for this determination, Cisneros has presented no direct evidence that the voice on the tapes is not his, nor that the statements attributed to him are inaccurate," Sporkin wrote.