THE SUPREME COURT ruled last Monday that any policeman who stops an automobile for any traffic violation can compel its driver to get out of the car under any circumstances. At first glance, the decision may appear to be relatively unimportant. The Court's majority apparently so regarded it; it disposed of the matter in an unsigned opinion without bothering to hear arguments. But the more we have thought about this decision - and the rationale on which it is based - the worse it seems to be. The Court was so eager to strengthn the hand of police that it violated a principle that has helped preserve personal freedom in this country: No longer will police be required to try to distinguish between criminals and everyone else before asserting their authority - as far as automobile drivers are concerned.

Now you may not regard being compelled to get out of your cars as an infringement on your personal freedom. The Court's current majority obviously doesn't. But let's look at some hypothetical situations. Suppose the night is especially dark and the street is deserted. You are stopped by a police car that may or may not be in uniform. Is it, as the Court says, "a mere inconvenience" in such circumstances to be forced to get out of your car? Or suppose it is pouring rain and you are stopped for having an outdated inspection sticker. Or that you are old or handicapped and getting out of the car is physically difficult.

We know that most policeman will never use the power that the Court has just said they have in such situations. But we know, and you do, too, that a few will - to flaunt their authority, to vent one prejudice or another or for malicious pleasure at inducing embarrassment. We raise these hypothetical cases because the Court has rarely given the police such unrestricted power. It usually requires a specific reason for a police officer to force an individual citizen to do something. We would not quarrel with a decision holding that police have authority to order out of their cars all drivers who are suspected of carrying a weapon or of having committed some crime more serious than a mere traffic violation. But the Court does not distinguish - and it no longer requires the police to distinguish - between the driver with four children in the car who has made an illegal turn and the driver who has led the police on a 100-mile-an-hour chase through downtown Washington.

The justification for his departure from tradition rests on the Court's having found that some drivers have guns and shoot policemen. That, regrettably, does occur. But it does not occur as frequently as the Court claimed it does. Nor are police departments as united as the Court seems to think in believing that the best protection against such shootings is to make drivers get out of their cars. Justice John Paul Stevens demolished both bases of the Court's finding in his dissent. The numbers in the study the Court used on shootings don't support its conclusion. Some law-enforcement agencies advice officers to protect themselves by keeping drivers inside their cars. The chosen to give thecase more than minimal consideration before reversing the Pennsylvania Supreme Court; no arguments were invited.

This is one of those situations in which the fact that the Court has said certain actions are constitutional does not mean those actions are right. The Pennsylvania court can still hold the practice in violation of that state's own version of the Fourth Amendment. State and local governments can, and should, pass legislation narrowing the authority the Court has said the police have.

The real problem is what this decision says about the values that now count with the current majority of the Court. The opinion takes seriously the claims of the police and waves off as frivolous the claims of personal liberty. This is not the first time the Court has done so recently and it is hardly likely to be the last. With this court the scales of justice, so far as the Fourth Amendment is concerned, are weighted heavily against the individual.