The Supreme Court put a dent yesterday in the absolute immunity that the Constitution provides to senators, representatives and their staffs "for any speech or debate in either house."

The justices let stand a ruling that the estate of Sen. John L. McClellan (D-Ark.) and three members of the staff of the Permanent Subcommittee on Investigations in the 1960s can be sued for $50,000 each in damages by Alan and Margaret McSurely.

The court gave no explanation why it had agreed not to rule in the case after hearing oral argument in which the government said that a congressional investigator pursuing a legitimate legislative purpose could break into a home and even kill someone.

Instead, the court simply issued an unsigned, one-sentence statement that it had "improvidently granted" a government petition to review the ruling by the U.S. Court of Appeals for the District of Columbia.

Sources said that the Supreme Court had ducked making a decision on the merits four months after hearing oral argument and after taking tentative votes and circulating draft opinions.

There was no clue as to the reasons, although factors that may have been taken into account included the deaths of three of the four defendants (McClellan and two of the subcommittee aides) and questions raised by recent decisions as to whether the appeals court ruling was truly final and therefore could be appealed.

Yesterday's action sets no controlling precedent. The lawsuit it permits may prove to be unique.

In a statement, the McSureley's said: "We look forward to this trial." They described themselves "as working people who have spent most of our lives in the fight against racism," and who thus came to be "relentlessly persecuted . . . for so long" by McClellan and his staff.

The case dates back to 1967, when a Senate resolution authorized McClellan to investigate causes of domestic disorder. At the time, the McSurelys were organizers for the Southern Conference Educational Fund.

Pike County authorities arrested the couple and seized papers in their home, including love letters to Margaret McSurely from her former employer, the late Washington columnist Drew Pearson. He addressed her as "Dear Cucumber."

A panel of three federal judges ruled that the state sedition law under which the arrests were made was unconstitutional and ordered impoundment of the seized papers. But the state prosecutor allowed a subcommittee investigator to copy the papers, including the love letters. These, the subcommittee investigator admitted later, weren't needed for legislative purposes.

In the lengthy litigation that followed, the McSurelys retrieved the papers and were convicted of contempt of Congress for disobeying a subpoena to give them up. The appeals court reversed the conviction.

The issue before the Supreme Court was whether to uphold the appellate court ruling that the McSurelys had a right to sue. The government argued that they did not because "speech and debate" had to provide legislative immunity even when a wrong was alleged. The McSurelys agreed that the immunity was absolute - but for normal legislative activity, not lawbreaking.

In other actions: LANDMARK PRESERVATION

The court ruled 6 to 3 that state and local governments can compel owners of private property to accept less compensation under laws to preserve historic landmarks than under laws permitting property to be taken for other public purposes.

New York City's refusal to allow the Penn Central Railroad to build an office tower above its Grand Central Station doesn't require the city to compensate the company because its development ban was not a "taking" of property under the city's landmark preservation law, Justice William J. Brennan Jr. wrote in the opinion for the court.

He noted that over the part half-century, all states and more than 500 runicipalities, including the District of Columbia and Loudon County, Val., have enacted laws to encourage or require the preservation of buildings and areas with historic or aesthetic importance.

The restrictions on development imposed by the New York law are "substantially related to the promotion of the general welfare," Brennan said. They "not only permit reasonable beneficial use of the landmark site but afford appellants opportunities further to enhance not only the terminal site proper but also other properties."

The city's Landmarks Preservation Commission designated Grand Central - completed in 1913 - a landmark in 1967. That action barred construction on the site or exterior alternation without commission approval.

Shortly after the designation, Penn Central began negotiations with a firm that planned to erect a 55-story office building atop the terminal and million during construction and $3 million afterward. The commission turned down the plan, was sued, and agreed to pay annual rentals of $1 prevailed in the state's highest court, which was upheld yesterday.

In the dissenting opinion, Justice William H. Rehnquist wrote that all of the city's taxpayers, not merely owners of a relatively few individual properties, must bear the cost of preserving landmarks. Chief Justice Warren E. Burger and Justice John Paul Ste- [TEXT OMITTED FROM SOURCE] SEARCH WARRANTS

Resolving what Justice Harry A. Blackmun termed "an important and longstanding issue of Fourth Amendment law," the court ruled, 7 to 2, that after a search warrant is issued, a defendant can challenge the truthfulness of statements in the warrant supporting it.

But if the defendant is to win a hearing at which he seeks suppression of evidence gathered under the warrant, the court held, he must make a substantial preliminary showing that a false statement was made knowingly and intentionally, or with reckless disregard for the truth. He must also show that the false statement was pivotal to the finding that probably cause existed for issuance of the warrant.

The court acted in a Delaware case involving the conviction of Jerome Franks for rape, kidnaping and burglary. Rehnquist, joined by Burger, dissented. SENTENCING

Settling a conflict among the federal appeals tribunals, the court ruled, 6 to 3, that when a trial judge notes false testimony by a defendant, he can take the perjury into account in fixing the sentence.

In a dissenting opinion, Justice Potter Stewart protested that there was "no determination" that false testimony actually had been given by the defendant, Ted R. Grayson. The result of the ruling will be that any defendant who testifies in his own behalf and is convicted will open himself to the possibility of an enhanced sentence, Stewart said. Burger wrote the opinion for the court.