Police officers cannot stop cars at random to see if they are unregistered, if the drivers are unlicensed, or if there are other possible law violations, the Supreme Court ruled 8 to 1 yesterday.

If an officer lacks at least a suspicion of wrongdoing that he can clearly express and is "reasonable," stopping a motor vehicle and detaining the operator for a registration or license check violates the guarantee in the Constitution against unreasonable seizures, the court held.

In a swift reaction, District of Columbia Police Cheif Burtell M. Jefferson rescinded a standing order permitting random spot checks, which also have been authorized in Maryland and Virginia.

In a message teletyped at 7 last night, Jefferson directed all officers of the Metropolitan Police Department to "cease and desist" making random spot checks unless they follow the "reasonable suspicion" standard adopted yesterday by the court.

In the opinion for the majority, Justice Byron R. White wrote, "An individual operating or travelling in an automobile does not lose all reasonable expectation of privacy simply because the automobile and its use are subject to government regulation. . .

"Were the individual subject to unfettered governmental intrusion every time he entered an automobile, the security guaranteed by the Fourth Amendment would be seriously circumscribed," White said.

As the court recognized in a 1968 ruling, White continued, "people are not shorn of all Fourth Amendment protection when they step from their homes onto the public sidewalks. Nor are they shorn. . . when they step from the sidewalks into their automobiles."

At the same time, White wrote, states remain free to develop methods for spot checks "that involves less intrusion or that do not involve the unconstrained exercise of discretion. Questioning of all oncoming traffic at roadblock-type stops is one possible alternative."

The court acted in a Delaware case that began on a November night in 1976 in Wilmington when a patrolman in a police cruiser stopped a car occupied by four persons. As the officer approached he smelled marijuana smoke; on the car floor he saw marijuana in plain view.

A New Castle County grand jury indicted William J. Prouse III, one of the car's occupants and also its owner, for illegal possession of a controlled substance.

Prouse filed a motion to prevent the marijuana from being used as evidence on the ground that it had been unconstitutionally seized. At a hearing, the officer testifed that before stopping the car he had seen no traffic or equipment violations or suspicious activity and had flagged it down only to check the driver's license and the registration.

"I saw the car in the area and was not answering any complaints so I decided to pull them off," New Castle Patrolman Anthony Avena said.

As White put it, Avena "was not acting pursuant to any standards, guide-lines, or procedures pertaining to document spot checks promulgated by either his department or the state attorney general."

Superior Court Judge Joseph T. Walsh granted the defendant's motion to suppress the evidence, saying that Avena had made a "capricious" stop in violation of the Fourth Amendment.

The Delaware Supreme Court upheld him with a ruling consistent with decisions made in several states, including New York and Pennsylvania, but inconsistent with decisions in several other states, including North Carolina and Nebraska. The U.S. Supreme Court agreed to review the Delaware ruling in order to resolve the conflict.

Only three weeks ago, while the Delaware case was under advisement, Maryland's court of Special Appeals ruled that police no longer may randomly stop cars for "routine checks," but instead must have a "reasonable suspicion" of a specific law violation. Earlier rulings of the same court had seemed to permit random stops, according to Assistant Attorney General Stephen Caplis.

In Virginia, spokemen for the state police and for various suburban jurisdictions withheld comment pending a review of the opinion. Generally, Virginia state troopers have been more inclined than city and county officers to make the types of stops that were outlawed yesterday.

One technique that might pass high court muster is a check of some but not all of the cars going by. Justice Harry A. Blackmun, joined by Justice Lewis F. Powell Jr., nothing that yesterday's opinion allows for spot checks that don't involve unbridled discretion, wrote in a separate opinion:

"The roadblock stop for all traffic is given as an example. I necessarily assume that the court's reservation also includes other not purely random stops (such as every 10th car to pass a given point). . . . "

In the dissenting opinion, Justice William H. Rehnquist pointed out that neither the majority nor the Delaware Supreme Court had suggested that Officer Avena's random stop had been racially discriminatory or otherwise violative of the 14th Amendment's guarantee of equal protection of the laws.

Thus, Rehnquist said, the majority's concern that random stops may entail "a possibly unsettling show of authority" and "may create substantial anxiety" seem to be "an insufficient basis to distinguish for Fourth Amendment purposes between a roadblock stopping all cars and the random stop at issue here."

In defending random stops, Delaware argued that the practical benefits outweighed the "minimal" intrusions on privacy. Justice White, however, found these benefits marginal at best.

Four years ago the court rejected a claim by the federal government that border patrol agents could stop at random any vehicle to determine whether it contained illegal aliens or was involved in smuggling.