Before he was stabbed to death in a bar fight in 1976 at age 35, Ernie Miranda eked out a living autographing the cards that police officers carry so they can read people their legal rights when they're arrested.

Ernesto Arturo Miranda was the eponymous Miranda of "Miranda Rights," the ones heard so often on TV cop shows, the ones that begin, "You have to remain silent. Anything you say can and will be used against you in a court of law...."

A career criminal, he spent most of his short life in various juvenile centers, jails, stockades and prisons, achieving fame thanks only to the U.S. Supreme Court's landmark 5-4 decision in Miranda v. Arizona in 1966.

On Monday, the high court, on another 5-4 decision, trimmed the scope of Miranda Rights, tilting the board in favor of police officers. In its decision in Berghuis v. Thompkins, the court ruled that if a defendant wants to remain silent, he has to speak up and definitively say so.

If he doesn't, police may continue questioning him. If he blurts out an incriminating answer, courts can construe that as a waiver of the right to remain silent and use the answer to try to convict him.

The effect of this on street-smart defendants will be minimal. Less-sophisticated suspects may nod their heads or sign a paper acknowledging that they've been read their rights. But unless they explicitly say they don't want to talk, police are free to continue questioning them.

That's what two Southfield, Mich., police detectives did after Van Chester Thompkins, arrested for a 2000 drive-by slaying, refused to sign a paper acknowledging he'd been read his rights. The detectives ignored his silence and kept after him for almost three hours until Det. Christopher Helgert asked Thompkins if he believed in God.

"Yes," Thompkins said.

"Do you pray to God to forgive you for shooting that boy down?" Det. Helgert asked.

"Yes."

That one word helped convict Thompkins, who received a life sentence. An appeals court struck down the conviction, ruling that Thompkins' lack of cooperation during the questioning meant that he hadn't waived his right to silence.

Justice Anthony Kennedy, writing for the Supreme Court's majority, disagreed. "Thompkins did not say that he wanted to remain silent or that he did not want to talk to police."

In a lengthy dissent, Justice Sonia Sotomayor noted that police were not likely to advise suspects of the precise "magic words" they had to invoke to protect their Fifth Amendment rights against self-incrimination.

Justice Sotomayor criticized the court majority's judicial activism in overturning 40 years of precedent. "Today's decision turns Miranda upside down," she wrote.

In the 44 years since Miranda, even though courts generally have sided with giving defendants fuller protection, prisons have remained full. Smart cops have the upper hand in dealing with suspects, most of whom — guilty or not — are not very bright.

Indeed, many police departments already instruct their officers to obtain an explicit waiver of Miranda rights before asking questions. It now would appear that they don't have to.

Many conservative scholars argue that under Chief Justice Earl Warren in the 1960s, the court went too far in reading rights into the Fifth and Sixth Amendments. Now, under Chief Justice John G. Roberts Jr., we seem to have just the opposite problem.

REPRINTED FROM THE ST. LOUIS POST-DISPATCH