U.S. Attorney Joseph E. diGenova called a lawsuit by District Mayor Marion Barry an "unbridled and unsubstantiated" attack on his investigation of D.C. government contracting and asked a federal judge to dismiss Barry's complaint, according to court papers made public yesterday.

Barry's suit, filed 11 days ago, accused diGenova of "prosecutorial vindictiveness" and of violating federal grand jury secrecy rules through leaks to the news media about the investigation of D.C. contracting practices.

In court papers unsealed yesterday by Chief U.S. District Judge Aubrey E. Robinson Jr., diGenova said Barry's claims of prosecutorial misconduct were "totally unsupported and . . . contradicted" by the news articles and broadcast reports he cited in his lawsuit.

DiGenova said that the Barry suit's "specious and unwarranted attack on the alleged actions of the U.S. attorney's office is actually a challenge to the criminal justice system itself."

"Beyond the recitation of various media reports, and his 'opinions' and 'beliefs' that certain disclosures must have come from the government, {Barry} offers nothing to support his virtually unprecedented attempt to interfere with the grand jury and prosecutorial investigative process," diGenova said in the court papers.

No new details about the scope or progress of the investigation were revealed by the federal government in its papers. However, the government attorneys said information about what the grand juries are probing could be submitted to the judge if necessary. Such a submission would be confidential and would not be provided to Barry or his attorney, according to the court papers.

Barry's attorney, Herbert O. Reid Sr., said yesterday he had no comment on the federal government's statements but indicated that he may soon file court papers in response.

In the lawsuit, Barry claimed that actions by diGenova and others in the current investigation have caused District employes to be "fearful of engaging in all manner of contracts and procurement activity" and have shaken confidence in his administration.

Barry asked Robinson for a preliminary injunction to block disclosures about the wide-ranging probe, which also is focusing on alleged payments to convicted cocaine dealer Karen K. Johnson in exchange for her not testifying to an earlier grand jury investigating alleged drug use by city officials, including Barry.

Barry's lawsuit asked the court to make public all evidence now before the grand juries, to require "good faith" affidavits to support all future grand jury subpoenas issued in conjunction with the probe, and to impose sanctions against diGenova, claiming he has violated the federal rule of grand jury secrecy.

Robinson has not said whether he will set a hearing on Barry's request for a preliminary injunction. The government's 51-page motion to dismiss the lawsuit contends that Barry has presented no evidence to show that news media reports are based on information supplied by the U.S. attorney's office.

Without such a showing, the lawyers argue, it is not necessary for federal officials to present evidence to demonstrate that information did not leak out of the prosecutor's office.

"Just because certain aspects of the District of Columbia government are currently under investigation, and this investigation understandably has attracted public scrutiny, {Barry} cannot seek to avoid these consequences by asserting his status as a public official," diGenova said in the papers.

"To countenance such an argument would be to sanction an absurd result, for no official of an administration could then ever be the subject of an investigation that might attract widespread adverse publicity," diGenova said.

The papers note that the grand jury secrecy rule applies only to information that could be obtained only from the grand jury and that the rule does not prohibit disclosures by witnesses.