Washington ? Want to invoke your right to remain silent? You’ll have to speak up.

In a narrowly split decision, the Supreme Court’s conservative majority expanded its limits on the famous Miranda rights for criminal suspects on Tuesday — over the dissent of new Justice Sonia Sotomayor, who said the ruling turned Americans’ rights of protection from police abuse “upside down.”

Justice Anthony Kennedy, who wrote the majority opinion, said a suspect who goes ahead and talks to police after being informed he doesn’t have to has waived his right to remain silent. Elena Kagan, who has been nominated by President Barack Obama to join the court, sided with the police as U.S. solicitor general when the case came before the court. She would replace Justice John Paul Stevens, one of the dissenters.

A right to remain silent and a right to a lawyer are at the top of the warnings that police recite to suspects during arrests and interrogations. But Tuesday’s majority said that suspects must break their silence and tell police they are going to remain quiet to stop an interrogation, just as they must tell police that they want a lawyer.

This decision means that police can keep shooting questions at a suspect who refuses to talk as long as they want in hopes that the person will crack and give them some information, said Richard Friedman, a University of Michigan law professor.

“It’s a little bit less restraint that the officers have to show,” Friedman said.

The ruling comes in a case in which a suspect, Van Chester Thompkins, remained mostly silent for a three-hour police interrogation before implicating himself in a Jan. 10, 2000, murder in Southfield, Mich. He appealed his conviction, saying he had invoked his Miranda right to remain silent by remaining silent.

Kennedy, writing the decision for the court’s conservatives, said that wasn’t enough.

“Thompkins did not say that he wanted to remain silent or that he did not want to talk to police,” Kennedy said. “Had he made either of these simple, unambiguous statements, he would have invoked his ‘right to cut off questioning.’ Here he did neither, so he did not invoke his right to remain silent.”

He was joined in the 5-4 opinion by Chief Justice John Roberts and Justices Antonin Scalia, Clarence Thomas and Samuel Alito.