The House yesterday overwhelmingly rejected a move to expel convicted Rep. Charles C. Diggs Jr. (D-Mich.). Diggs agreed with the majority, voting for himself over a tart Republican protest.

By a vote of 322 to 77, the House voted instead to consign the problem to the House Committee on Standards of Offical Conduct, or ethics committee, for further study.

Diggs, convicted last fall of 29 counts of taking salary kickbacks from his staff and sentenced to three years in prison, sat in a prominent position behind a speakers' table throughout the sometimes dramatic debate. He voted both on a procedural question and against his own expulsion.

The first Diggs vote, on a procedural issue, brought Minority Leader John J. Rhodes (R-Ariz.) leaping to his feet to raise a point of order against Diggs' casting a vote. Rhodes cited a House rule that prohibits a member from voting on a matter in which he has a direct personal or pecuniary interest.

House Speaker Thomas P. (Tip) O'Neil Jr. (D-Mass.) overruled Rhodes' point of order on the grounds that under House precedents, it was up to the member himself to decide when he had a conflicting personal or pecuniary interest in a matter.

It was that smae issue -- whether Diggs should vote in the House while his conviction is being appealed in the courts -- which prompted the expulsion motion by freshman Republican Newt Gilngrich of Georgia.

Gingrich indicated he would have waited for the ethics committee to act if Diggs had not voted Wendnesday on a bill to raise the debt ceiling by $38 billion. Gingrich said permitting "for an indefinite period a convicted felon to vote on the laws of the United States" bothered him. If a law was passed by just one vote, that of a convicted felon, "How could we go home and uphold the sanctity of the U.s. h/ouse?" Gingrich asked.

But in an impassioned speech, Majority Leader Jim Wright (D-Tex.) said expulsion was "the most severe punishment the House can bestow." He noted that only three members had ever been expelled in the history of the House, all in 1861 for the treason of joining the Confederate Congress.

Wright said Diggs had not exhausted his appeals and noted that just recently four public officials, including Maryland Gov. Marvin Mandel and Florida's former senator Edward Gurney, had their convictions overturned on appeal. He said Diggs had not been accorded due process in the House since the ethics committee had not investigated or allowed Diggs to respond to charges. And finally he argued that the constituents of Diggs' district, who reelected him after his conviction, had an almost unlimited constitutional right to be represented "by a person of their choice."

Wright asked the House to "consider the sanctity of the House, the sanctity of the Bill of Rights and the sanctity of due process," and reject expulsion.

Rep. Peter Kostmayer (Ap.) was the only Democrat to argue for expulsion. He said Diggs was "arrogant to continue to insist on voting... I can't imagine the average American who stole $70,000 being extended such courtesies."

The ethics committee chairman, Charles E. Bennett (D-Fla.), said he has already hired an attorney to begin an investigation of the Diggs matter, and after talking with the attorney has concluded that the investigation could be completed in "30 to 40 days, certainly in 60 days."