Twenty years ago today Chief Justice Earl Warren announced from the bench of the U.S. Supreme Court new guidelines on whether a defendant's confession could be admitted as evidence in a criminal trial.

It took him more than an hour to read the entire 61-page opinion, but the heart of the court's message in the case of Miranda v. Arizona was in four sentences that dictated police conduct for interrogating suspects in custody.

The Miranda decision set off a national uproar among law enforcement officials, was soon the target of congressional attempts to invalidate the decision and ultimately provided the law-and-order theme of Richard Nixon's 1968 presidential campaign.

Today, it's simply the law of the land, and while still under attack by critics such as Attorney General Edwin Meese III, most law enforcement authorities say they long ago learned to live with it.

"The initial reaction of police and police officials was that it was the end of justice," Montgomery County Police Chief Bernard D. Crooke said this week. "I'm sure it was overreaction, but we thought it was ludicrous, ridiculous, [and] that police would be handcuffed.

"In reality, we were able to adjust . . . . We weren't handcuffed," said Crooke, who in 1966 was a D.C. police homicide investigator. Nevertheless, he added, "some guilty people walked free" because of the court's ruling.

"Police had to work harder, they had to be better trained as investigators, and that's not wrong either," said Crooke.

"We must have done something right, because we have filled up every jail in this country."

The four critical sentences of the ruling: "Prior to any questioning, a person must be warned that he has a right to remain silent, that any statement he does make may be used against him, and that he has the right to the presence of an attorney, either retained or appointed," the five-member majority said.

"The defendant may waive . . . these rights, provided the waiver is made voluntarily, knowingly and intelligently. If, however, he indicates in any manner and at any stage of the process that he wishes to consult with an attorney before speaking there can be no questioning.

"Likewise, if the individual is alone and indicates in any manner that he does not wish to be interrogated, the police may not question him."

The latest of a series of decisions that expanded the rights of accused persons, the opinion that Warren delivered that Monday morning was extraordinary for its detailed instructions to police and for his repeated assurances that it would not hamper effective law enforcement.

Supporters and opponents of the decision and subsequent modifications, agree that its enforcement has largely cured the problem the justices sought to overcome: lengthy and physically or psychologically brutal questioning by police used as a way to compel a suspect to confess to a crime.

Even young children have memorized the so-called Miranda warning, learning it by rote from television programs such as "Hill Street Blues" and "Miami Vice."

"The law has fallen into the mainstream and has been accommodated," said Gerald M. Caplan, a George Washington University law professor and author of a 59-page article titled "Questioning Miranda" that was published last fall in the Vanderbilt Law Review.

Caplan, who served as general counsel to the D.C. police department in the late 1960s and in 1971-72, described his article as mostly an academic or intellectual exercise and said that despite a call by Meese for repeal of Miranda, there is no active movement to support the attorney general's quest.

Caplan argues that Miranda changed the basic nature of police interrogation from being "fundamentally a moral process" to something of a sporting proposition or "game theory in which the state and the accused are seen as having equal moral worth."

Caplan argues that Miranda also shifted the public perception of criminals from that of a "species apart" to "members of the community who had gone astray."

Charles Morgan Jr., for two decades a civil rights lawyer in the South who is now in private practice here, says that the shift in perception was needed.

"The importance of Miranda was that it was symbolic in the sense that it said to the nation and the world and there is a check and a rein on the police . . . , " he said. "It was also the first time that the government was seen as a lawbreaker, and the court set specific rules for the government to follow.

"Though the government had probably been a lawbreaker before . . . it was the first time that 'the system' had said it was supposed to be hard for prosecuting attorneys to get convictions."

Yale Kamisar, a University of Michigan law professor who is considered the leading constitutional authority on the Miranda decision, pointed out that law enforcement officials had sought guidelines from the Supreme Court after its 1964 Escobedo v. Illinois decision. In that case, on a 5-to-4 vote, the court threw out the confession of a man who repeatedly asked to consult with counsel during questioning but was denied access to his lawyer.

Until the Escobedo and Miranda cases, the rule for determining whether a confession had been given voluntarily was based on the "totality of the circumstances," an approach that Kamisar said was completely unworkable because "every factor was relevant and none was decisive."

Alluding to a recent opinion by Justice Sandra Day O'Connor in a case that slightly modified Miranda, Kamisar agreed that over the last 20 years "Miranda has struck the balance between doing everything possible to keep a guy from confessing to letting him know that he doesn't have to."

Prominent local defense lawyer Plato Cacheris said he doesn't believe that warning suspects of their rights has had a major impact on the number of people who talk to police or on police conviction rates.

"Despite warnings, people continue to talk," he said. "And just because every suspect doesn't talk to police, it doesn't prohibit successful prosecutions."

G. Allen Dale, who works as a court-appointed attorney in many cases, said he believes most egregious instances of prolonged police questioning have been eliminated because of Miranda. Today his clients -- after asking for counsel -- are more likely to face subtle persuasion from police.

The police "say things like, 'We can make it easy on you if you talk now,' " Dale said. "Most people don't know that cops can't cut a deal."

The lag between the time a suspect asks to see a lawyer and the time he is able to consult with a lawyer also encourages some suspects to talk. "Even the richer clients aren't going to be able to get a lawyer out in the middle of the night," Dale said. "Sitting in jail, waiting to go to court, and not being able to see a lawyer for hours, many people decide to talk."

In a recent case, Dale said, between the time a suspect was arrested and when he was able to consult with him 10 hours later, the man had confessed to four bank robberies.

Defense lawyer Fred Joseph, who represents nurse Jane Bolding -- who was questioned in March 1985 for about 24 hours concerning the death of a 70-year-old woman at Prince George's General Hospital -- believes that the instances of illegal questioning by police are increasing.

He said, "With Attorney General Meese advocating the reversal of Miranda, that permeates down to the cop on the beat, who thinks that he is merely carrying out that which my president and my attorney general want me to do."