IT IS TIME to allow the police to engage in well-intentioned violations of our rights, to search our homes, our cars, our papers or anything else so long as they do it in "good faith." That is the essence of the momentuous argument the Supreme Court will hear on Tuesday from opponents of the "exclusionary rule," which bars from criminal trials any evidence the police seize illegally.

Opponents of this rule are legion, because so many citizens have been led to believe that disallowing such evidence crimps law enforcement and keeps large numbers of criminals roaming their neighborhoods. Both beliefs are nonsense, even if well- meaning nonsense.

As my former fellow cops on the street know, the exclusionary rule is simply irrelevant to almost all police work. Illegally seized evidence plays no part in the overwhelming majority of prosecutions, and in instances when it does, the rule barring its use in the courtroom rarely has any effect.

There are several reasons for this, but most notable is the fact that trial court almost always judge the legality of a search on the testimony of the officer who conducted the search -- and police who conduct illegal searches do not go around admitting that on witness stands.

It should be no surprise, then, that a study a few years ago by the Office of Management and Budget showed that motions to suppress evidence were successful in a mere 0.4 percent of all felony cases in federal courts. More recently, a National Institute of Justice study examined 874 burglary, robbery and assault cases in San Diego and Jacksonville, Fla. Its finding: A grand total of nine burglary cases were dismissed because of illegal searches and seizures, and not a single robbery or assault case was affected at all.

It would be a profound mistake, therefore, for the Supreme Court to view the case it will hear on Tuesday as in any way typical. That case -- involving a couple accused of possessing 400 pounds of marijuana, some cocaine, guns, ammunition and drug paraphernalia -- clearly falls in the minute minority.

The legal problems of the couple, Lance and Sue Gates, began on May 3, 1978, when an anonymous letter to the Bloomingdale, Ill., police said that they made "their living on selling drugs," and that they would soon be traveling to Florida and returning with "over $100,000 in drugs" in the trunk of their car.

Federal authorities tracked Gates on a flight from Chicago to a West Palm Beach motel, where he spent the night in a room registered to his wife. He and "an unidentified female" rose the next morning and entered a car bearing an Illinois plate registered to another auto he owned.

The Bloomingdale police did not attempt the simple next step of observing the couple unloading bales of marijuana from their car trunk, which would have provided firm ground for a search warrant. Instead, they sought a warrant on the basis of the anonymous letter and the travel observations, neither of which showed any violation of law other than the improper license plate.

Despite this, DuPage County Circuit Court Judge S. K. Lewis found that there was "probable cause" -- enough information to conclude that evidence of a crime was in the place described -- and granted a warrant to search the Gates home and auto. The search was conducted when the couple arrived in Bloomingdale, and the evidence was discovered.

At the trial, DuPage County Circuit Court Judge William W. Hopf ruled that Judge Lewis had erred in finding probable cause and that his search warrant was invalid. He excluded the drugs and other evidence, and the prosecutor's case collapsed.

The prosecutor appealed to the Illinois Supreme Court, which affirmed, 5 to 2, that the warrant was invalid. Hence in two days, Illinois Attorney General Tyrone C. Fahner -- supported by friend-of-the-court briefs from other law enforcement officials, including the Reagan Justice Department -- takes his argument against the Gateses and the exclusionary rule to the Supreme Court.

According to his brief, Fahner will urge the Supreme Court to rule, at the least, that the Gates warrant was valid and that the evidence obtained under it should be admitted. Winning this argument might eventually convict the Gateses; unfortunately, it would also expose the rest of us to house and auto searches based on anonymous letters and fruitless police observations.

Fahner's side might view such a victory as an accomplishment of sorts, but this is not their broad purpose. Fahner and those who have joined his argument with amicus curiae briefs are seeking something far more profound: Supreme Court sanction of well-meaning but illegal police searches and seizures.

Under the standard they propose, courts would have to determine that police had acted in a willfully unconstitutional way for the resulting evidence to be barred from a trial. The evidence would be admissible, however, if police, on their own or with warrants, search homes or offices or other property and seize property in "reasonable," "good faith" violations of citizens' rights.

Indeed, some Fahner supporters -- attorneys general of 31 states -- "emphatically submit that the rule should never be applied in cases involving duly issued warrants, absent a clear showing of fraud by (police who sought the warrant) or the unreasonable execution of the warrant."

Their briefs make some familiar points, particularly the contention that the exclusionary rule encourages "the ever expanding criminal component of our society" and results in the freeing of great numbers of criminals. But their arguments for the "good faith" exception, while reasonable- sounding on their face, generally ignore the real world -- at least the world I know from 16 years as a New York City police officer and from my work with police officers throughout the country.

In the real world police chiefs, under great pressure to reduce crime, pass that pressure on to officers, evaluating them almost exclusively by how many arrests and convictions they chalk up. Some officers -- though not most -- respond by overlooking constitutional niceties and conduct willfully illegal searches.

Most of the targets of these searches are not suburban couples like the Gateses. Many are young people on inner-city streets who are summarily directed to "assume the position" and submit to a search. Others are young drivers whose autos are searched. While police sometimes discover marijuana in pockets or car trunks, more often nothing is found. The targets are simply left humiliated, resentful and -- since cops are not foolish enough to do these things before audiences -- without means of proving what happened.

To whom can they complain? To police chiefs who have encouraged such searches? Who would take their word over the officers'?

And what happens when the target of an illegal search is found to have something illegal? Do the cops involved tell what really happened? Or, as one study suggests, do they sometimes testify that a suspicious-looking subject conveniently dropped the evidence to the ground, or that it fell out of the defendant's glove compartment when he reached for his driver's license and registration?

Suggesting that trial courts can distinguish between "good faith" mistakes and "willfully" unconstitutional searches requires us to believe that officers who abuse their power will expose themselves to disciplinary action and civil liability by testifying truthfully. That is a hopelessly naive belief.

This is also why it is disingenuous to argue, as one supporting brief does, that there is no evidence of abuse of the "good faith" exception in the two federal court circuits that have adopted it. That evidence, too, must come from the testimony of abusive officers, who are not going to provide it.

The contention that the exclusionary rule is letting all those criminals prowl our streets is another fiction. One of the Fahner supporters' own briefs, for example, quotes selectively from a study of the exclusionary rule's effect in California during 1976-79, but it omits the bottom line: Exclusion of evidence resulted in dismissals in only 1 or every 2,500 reported violent felonies in that period.

In short, where searches without warrants are concerned, the "good faith" exception would have little or no effect on police practices or crime. It would just give abusive officers a safer way around the Fourth Amendment and encourage more violations.

Equally, if not more, troubling is the suggestion that evidence obtained pursuant to search warrants never be excluded from trials. That would place an astonishing degree of faith in the magistrates who issue warrants. Indeed, it would make them the court of last resort on this question, a frightening prospect when one considers the quality and practices of many magistrates.

There are jurisdiction, to be sure, where search warrant practices are superb. Here in Washington, the police obtained and executed more than 400 warrants to search for evidence of narcotics and vice offenses last year. In New York City, the police executed more than 2,100 warrants related to narcotics, vice and auto theft offenses. In neither of those departments can the people who process warrants recall any incident in which evidence seized under their authority was excluded at trial. This is because warrants are issued only after careful consideration in Washington and New York.

But that is not true in many areas. In 26 states, magistrates who issue warrants are not even required to be attorneys. In many places they work on a part-time, piecework basis. In some places they are reported to have left blank, signed search warrants with their clerks -- or even with prosecutors -- to use as they see fit.

As President Nixon's National Advisory Commission on Criminal Justice Standards and Goals stated, our lower courts in general attract "judges of a lower caliber," dispense "assembly-line justice," and often operate "with improper procedures and under erroneous assumptions of the substantive law."

The 31 state attorneys general overlook all this when they "emphatically submit" that the exclusionary rule never be applied in warrant cases. It is troubling to ponder the consequences of effectively forbidding any review of the search warrants magistrates grant. It is not hard to imagine a great increase in warrants issued on questionable evidence, a growing number of searches that turn up nothing, even greater alienation from the system among the targets of such searches, and a dramatic erosion of all our rights.

Thus, opponents of the exclusionary rule are advancing a proposal that would do little -- except kill a safeguard against official arbitrariness. At best, their case might be termed a "good faith" mistake.