In Berghuis v. Thompkins (2010), the U.S. Supreme Court (by a 5-4 vote) continued to tinker with its Miranda decision with the gusto of a model train enthusiast who gets a new layout part. In this latest case, the Court made it a bit easier for prosecutors to offer confessions into evidence.
Here's what happened. Police officers advised murder suspect Thompkins of his Miranda rights to silence, to talk to a lawyer, etc. Thompkins didn't say much of anything in response. He didn't demand a lawyer, nor did he tell the police that he wanted to remain silent. Nor for that matter did Thompkins agree to talk to the police. So the police simply went on with their interrogation, and after almost 3 hours of doing little more than grunting, Thompkins finally admitted that he prayed to God for forgiveness for killing the victim.
The Court decided that the state had the right to offer Thompkins' statement into evidence at trial. Suspects can give up their Miranda rights simply by not invoking them but instead continuing to allow police questioning to continue. The police are not required to obtain written or even oral waivers from suspects in order to elicit valid confessions.
The dissenters argued that Berghuis is inconsistent with the Court's prior decisions and that it substantially waters down Miranda's protections. While recognizing that prior decisions did not demand an explicit written or oral waiver, the dissenters argued that the state failed to sustain its heavy burden of showing that Thompkins voluntarily gave up his right to remain silent.
From its inception in 1966, Miranda has been controversial. It has not had the dire consequences for successful prosecutions that its attackers predicted, largely because most suspects voluntarily waive their right to remain silent. Thus, Berhuis will probably not have a big impact on the number of confessions that are admitted at trial. However, when defendants neither explicitly waive their right to silence nor demand to talk to a lawyer, the case does enhance the likelihood that a suspect's damaging statements will be admissible at trial.