The Senate voted yesterday to prohibit the Justice Department from seeking school busing to achieve desegregation.

The rider to the department's appropriations bill has already been approved by the House, and a presidential veto may be required to remove it.

The rider, if strictly obeyed by the department, would prevent it from either initiating school desegregation lawsuits with busing as a remedy or interventing in suits brought privately.

It would, in effect, taking the U.S. government out of the busing field, curtailing two decades of Justice Department efforts to bring about desegregation in major U.S. cities.

Joseph Rauh, who represented the NAACP Legal Defense Fund in unsuccessful court suits to nullify such riders attached to Department of Education appropriations, called yesterday's action "unconstitutional as hell, patently unconstitutional. The Supreme Court has said we have to desegregate the schools even if it requires busing.

This rider says we must leave the schools segregated."

Rauh and other Legal Defense Fund officials said they were shocked that the Senate passed the rider yesterday on a 49-to-42 vote. The House has previously approved such measures, but they have always died in the Senate.

In fact, the Senate Appropriations Committee had deleted this Year's antibusing amendment, which prohibits the use of funds "to bring any sort of action to require directly or indirectly the transportation of any student to a school other than the school which is nearest the student's home." But the full Senate restored it yesterday.

Busing, said Sen. Jesse A. Helms (R-N.C.), an amendment sponsor, "has been a colossal flop. It has deteriorated the quality of education. We are harassing and intimidating the children."

Antibusing forces in the Senate turned to the Department of Justice appropriations bill after the court fight over the rider to the Health, Education and Welfare measure last year. The U.S. Court of Appeals here ruled that the rider was constitutional, but only because the Justice Department was still able to enforce the law.

The rider on the Justice appropriatin would change that situation.

Rauh said desegregation proponents would first urge the president to veto the amendment, and, if that failed, urge the Department of Justice to ignore it.

The senators would then undoubtedly bring their own suit in court against the Justice Department to demand enforcement.