BALTIMORE, OCT. 23 -- Federal prosecutors disputed today assertions by former Maryland governor Marvin Mandel and five associates that a recent Supreme Court ruling should be applied retroactively to overturn their mail fraud and racketeering convictions 10 years ago.

In a 57-page response filed in federal court, prosecutors brushed aside arguments that the Mandel case was similar to a case overturned by the Supreme Court in June. In that case, the high court held that mail fraud prosecutions against state officials can be made only when the fraud causes economic loss and not simply the intangible loss of good governance by the officials.

The whole case against Mandel, prosecutors said, involved bribery and the heaping of money, jewelry and free vacations on Mandel by secret business associates in exchange for the governor's political influence in getting lucrative horse racing legislation through the General Assembly for them.

It involved a "sordid tale of corruption, bribery and deceit at the innermost sanctum of state government," wrote U.S. Attorney Breckinridge L. Willcox. It was "both a state and federal crime in 1977 and remains so today."

Mandel was convicted of 15 counts of mail fraud and one count of racketeering in an alleged scheme to increase the value of Prince George's County's Marlboro Race Track in 1972 and 1973, then secretly owned by Mandel's codefendants, W. Dale Hess, Harry W. Rodgers III, William A. Rodgers, Irvin Kovens and Ernest N. Cory.

Mandel, according to prosecutors, helped the track obtain extra racing days, which are controlled by the state and worth millions of dollars in profits for track owners.

Mandel was imprisoned for 19 months. The codefendants were sentenced to terms ranging from 18 months to four years.

In June, the Supreme Court decision in McNally v. U.S. upset years of federal mail fraud prosecutions by ruling that the fraud statute was meant to apply to fraud involving property or money, not such concepts as the "intangible right of the citizenry to good government."

In August, attorneys for Mandel and his codefendants asked the federal court here to review their conviction in 1977 in light of the Supreme Court ruling.

They contended that the racketeering charge and the underlying mail fraud counts were based on the "intangible rights" theory and thus they were "convicted and punished for acts that the law does not make criminal."

In his response today, Willcox scoffed at the comparison of Mandel's situation to the Supreme Court case, saying Mandel's attorneys were "relying on an expansive reading of . . . McNally."

Willcox added: "To allow these defendants to capitalize now on McNally, at a time when retrial is impractical, would derogate the criminal justice system and create the appearance that the defendants have been vindicated, notwithstanding the clear criminality of their conduct."

Even if the new McNally standards were applied retroactively, Willcox said, Mandel and the other defendants still would be convicted because of the tangible nature of their fraud.

Marylanders were deprived of property rights in two ways, Willcox said: the bribes received by Mandel and the value of the racing dates obtained for the Marlboro track.

Arnold Weiner, Mandel's attorney, could not be reached.