Former Maryland governor Marvin Mandel and his five codefendants, taking advantage of what may be their last chance to avoid prison, asked the U.S. Supreme Court yesterday to overturn their 1977 political corruption convictions.

In their request, Mandel and his associates directed a new attack at the legality of the 4th U.S. Circuit Court of Appeals tie vote that upheld the convictions last July.

They called the decision a "usurpation of power" by a minority of the appeals court judges that could create a "most dangerous precedent" and imperil "the whole notion of majority rule . . ." in the courts.

Their new argument raised questions about the entire federal appellate process never before resolved by the Supreme Court.

It also raised the first real glimmer of hope among the defendants that the court might consider their case, since the justices generally are far more incluned to deal with important new questions than to rehash relatively old ones, such as Mandel's other contentions.

Federal prosecutors have 50 days to respond to yesterday's appeal. It could be weeks or months after that before the Supreme Court acts. A decision against the six men most likely would result in the immediate carrying out of the sentences imposed in Octover 1977 by U.S. District Judge Robert Taylor.

Taylor gave then-governor Mandel a four year prison sentence. W. Dale Hess, Harry W. Rodgers III and Irvin Kovens, all close and wealthy friends of Mandel's, received four-year sentences and fines of $40,000 each. William A. Rodgers, another Mandel associate and the brother of Harry Rodgers, received a 20-month sentence and a $40,000 fine. Laurel lawyer Ernest N. Cory Jr., an employe but not an intimate of the others, was sentenced to 20 months in jail.

A jury convicted Mandel and his businessmen friends on mail fraud and racketeering charges, stemming from a complicated scheme by which Mandel allegedly used his office and the state legislature to enrich the others in exchange for a series of financial favors. At the center of the scheme was the now defunct Marlboro Race Track in Prince George's County that received lucrative benefits from the Mandel administration while secretly owned by Hess, the Rodgers brothers and Kovens.

Much of the appeal filed yesterday focuses on legal question about those charges and Judge Taylor's conduct of the trial, including his instructions to the jury. Those arguments were raised before the 4th Circuit Court after the sentencing.

The procedure by which the 4th Circuit Court handled those arguments was the subject of the new attack filed yesterday as a separate request for corrective action directed at the appeals court. The court's behavior, said lawyers for Mandel and the others, "can only be described as cruel and unusual appellate justice."

Ordinarily, under federal law, a tie vote in an appeals court automatically affirms the decision of the next lowest court. But in the Mandel case, the 3-3 vote of the full 4th Circuit Court was allowed to reverse the action of a three-judge appeals panel that had previously nullified the convictions. The convictions and the jail terms were thus reinstated.

The action was "both remarkable and unparalleled in the history of the federal judicial system," the defendants' lawyers told the Supreme Court.

. . . Never before in the annals of the federal judiciary has less than a majority of participating judges sought to exercise affirmative judicial power. Never before has an equal division of active circuit judges usurped judicial power by rendering a judgment totally inconsistent with a valid panel judgment.

". . . This breakdown in appellate justice cries out for review and correction by" the Supreme Court.

The lawyers asked the Supreme Court to in effect reinstate the three-judge panel's decision setting the men free. That would return the entire case to federal prosecutors, who would then have to decide whether to go through a third trial. A first Mandel trial ended in a mistrial after jurors were exposed to publicity concerning two jury-tampering efforts.

The court also has before it two separate appeals filed yesterday: one from Mandel, Hess, William Rodgers and Kovens as a team and another from Cory and Harry Rodgers.

The court now has a wide range of possibilities before it. It could simply refuse to consider any of the pleas, at one extreme and the men would most likely be ordered to jail.

Or, at the other extreme, it could wipe out all the convictions in such a way that they could not be raised again, ending for good a labyrinthine judicial odyssey that began with Mandel's indictment more than four years ago. j