Claiming that prosecutors' charges against their client are too vague, lawyers for William L. Cowhig yesterday refused to file a pretrial rebuttal of the case against the indicted Alexandria commonwealth's attorney.

"Since no specific dates, times or places have been set out by the commonwealth, it is impossible at this time to furnish the commonwealth alibi information," a defense statement filed in Alexandria Circuit Court said.

"At such time dates, times and places are adduced, the defense will furnish any and all information which it intends to rely upon."

Special prosecutor Edward J. White could not be reached for comment.

The defense has argued consistently that the bribery indictment against Cowhig is vague, and White has twice filed court papers giving details of the prosecution's case. A defense motion that the charges be dismissed on grounds of vagueness was denied by Prince William Circuit Judge Percy Thornton.

On Wednesday prosecutor White had filed documents that alleged that Cowhig had deposited nearly $9,000 more than he earned in salary in his bank account. Yesterday an attorney for Cowhig, James M. Lowe, was quoted by the Associated Press as saying that the extra funds deposited by Cowhig can be attributed to legitimate sources such as income tax refunds, money from an old business investment, and legal fees left over from his private law practice.

Thornton will preside over the trial, set to begin next Tuesday. Cowhig is accused of accepting $32,000 in bribes from the director of the Montessori School of Alexandria in exchange for overlooking alleged bingo game irregularities.

Yesterday's filing included a list of 89 potential defense witnesses, a virtual who's who of Northern Virginia's political and legal communities.

Included were Alexandria Mayor Frank Mann, Fairfax County Commonwealth's Attorney Robert F. Horan Jr., Alexandria City Attorney Cyril D. Calley, acting Alexandria prosecutor John Kloch and Alexandria Police Chief Charles Strobel.

The defense also named Roger L. Amole, president of the Alexandria Bar Association, former state House majority leader James M. Thompson, state Del. Gary R. Myers (R-Alexandria), Republican state Sen. Wiley Mitchell, deputy city attorney Burton B. Hanbury Jr., all assistant Alexandria commonwealth attorneys, former Alexandria police chief John B. Holihan, Democratic Rep. Herbert E. Harris II and Cowhig's stepmother, Mary Colasanto.

The defense also said it plans to introduce Cowhig's financial and bank records, including records from the resort hotel Cowhig and his family own in the Bahamas.

In a separate development yesterday, William H. Fields pleaded no contest to three misdemeanor counts of aiding an illegal gambling operation in the form of bingo. Fields had been indicted last Aug. 3 on a felony count of running an illegal gambling operation.

Fields, who stepped saide as the administrative assistant to Alexandria City Councilman Nicholas A. Colasanto, was fined $1,500.

Attorney James I. Burkhardt, who represented bingo operator George Leonard Berry at Berry's gambling trial last month, yesterday criticized the Fields plea. "I begged (special prosecutor Edward J.) White for a misdemeanor plea, but he wouldn't agree to give it. There should be equal treatment for all these people, not misdemeanor pleas for some and jury trials for others," Burkhardt said.

Berry was sentenced to two years in prison and fined $15,000 following a four-day trial in Alexandria Circuit Court.

Berry, who also faces gambling charges in Fairfax County, said yesterday he has requested a nonjury trial in that case. He has pleaded innocent to the charges.