"You are under arrest. You have the right to remain silent. Anything you say can be used against you in court. You have the right to talk to a lawyer for advice before we question you and to have him with you during questioning. If you cannot afford a lawyer and want one, a lawyer will be provided for you." Twenty years ago this month, the Supreme Court told police that these assurances must be given to suspects in custody before questioning begins. These familiar Miranda warnings -- named for the case in which they were set out -- are known to every 12-year-old who watches cops-and-robbers TV. The words have been memorized and accepted and are carried in writing by every police officer in the country.

It may be difficult to understand why warnings that are so routinely given today were once thought to be so revolutionary. Before 1966, suspects were sometimes arrested and held for long periods of time, unable to communicate with family or legal counsel. They might not have been physically abused, but they were often young, confused and ignorant. Some were also innocent, but they confessed to crimes for reasons having to do with the psychological pressures of station house interrogation. So long as such confessions were "voluntary," they were admitted in evidence. This is the standard to which Attorney General Meese would have the country return today.

The court has just tacitly reaffirmed Miranda by refusing to hear an appeal in an Alabama case. That state's supreme court had held that a statement made by a murder suspect was inadmissible because it was made before he had explicitly or implicitly waived his rights. He will now be retried; the statement cannot be used against him.

Many people, including the attorney general, believe that foul-ups of this kind occur all the time and that many guilty parties are not brought to justice because of the technicalities imposed by Miranda. But there is no statistical evidence to back up this charge, and most police and prosecutors just don't believe it. Yes, police must be careful in reading the warnings and making sure the suspect understands and knowingly waives his rights, but it's done all the time.

As Montgomery County Police Chief Bernard Crooke said last week, " After Miranda police had to work harder, they had to be better trained as investigators, and that's not wrong either." Suspects continue to confess, even after receiving the warnings, and cases continue to be made without confessions. But now it is reasonably certain that incriminating statements admitted in evidence have been made voluntarily and are true. That is what the court ensured in Miranda two decades ago.